Enhanced presentation compiler test infrastructure

* Removed unneeded .flags.
* Renamed a few methods in `InteractiveTest`.
* Force the presentation compiler to shut down after each test.
* -sourcepath in the .flags file is now relative to the test's base directory.
* Use `InteractiveReporter` in Presentation Compiler tests.
  By using the `InteractiveReporter`, compilation errors are collected in the
  compilation unit. This was necessary for testing SI-5975.
Allow attachments for symbols, just like for trees.

Removes the two global hash maps in Namers, and the one in NamesDefaults. Also fixes SI-5975.
SI-5974 make collection.convert.Wrappers serializable
macro-based string interpolation formatter

This commit provides a macro based string interpolation formatter.
The macro is implemented in MacroImplementations.scala.

In order to still be able to build a new STARR, the implementation
in StringContext.f is not yet changed. This will be replaced in
a later commit.
adds the sha1 files of the new starr / stringContext.f

This commit provides the new sha1 codes of the new STARR.
Moreover, it replaces the implementation of StringContext.f
to `macro ???`. The implementation is magically hardwired into
`scala.tools.reflect.MacroImplementations.macro_StringInterpolation_f`
by the new STARR.
stringinterpolation macro test files

This commit adds test files
neg: checks the error messages generated by the compiler
run: checks the macro implementation features
Fixed replacestarr to use packed libraries and also include source files.
Added opt variant to replacestarrwin
removes special case for BigInteger

After rebasing, the commit 34d36108bf is in the history, therefore
a patch in my code can be removed as an implicit conversion from
BigInteger to BigInt was added in commit 34d36108bf.
The tests cases test this case and still pass.
Implicits to encourage more Name-dropping.

This creates implicits in cakes across the land from:

  String => TermName
  String => TypeName

And also from:

  Name => NameOps[Name]           // lower priority
  TermName => NameOps[TermName]
  TypeName => NameOps[TypeName]

What this is all about, using "drop" as a motivating example,
is that these should all work:

  "abc" drop 1                      // "bc": String
  ("abc": TermName) drop 1          // "bc": TermName
  ("abc": TypeName) drop 1          // "bc": TypeName
  (("abc": TypeName): Name) drop 1  // "bc": Name

But this should not:

  ("bc": Name)  // ambiguity error

This requires drop not being directly on Name; peer implicits
from String => TermName and String => TypeName; implicit
classes to install drop on TermName and TypeName; and a lower
priority implicit class to allow ops on Names.

Review by @xeno.by .
SI-6042 Improve type selection from volatile type error

 - Display the type of the typed qualifier (qual1), to avoid the
   message "Illegal type selection from volatile type null".
 - Show the upper bound, which is used to calculate the volatility.
Added a HIDDEN flag.

[Still not a fan of the massive overlap between GenJVM and GenASM. I do
not think such duplication should be allowed into master at all, neither
in experimental backends nor anywhere else. Putting us in the position
that we have to actually switch to stop incurring the duplication is
engineering-by-prayer.]

The SYNTHETIC flag was long ago discovered to be inadequately specific
to allow for emitting ACC_SYNTHETIC in bytecode. In this commit is born
a HIDDEN flag, which signals the flagged symbol as implementation detail
which should not be considered during typechecking, and which will
receive ACC_SYNTHETIC during code generation.

Unsure what should be hidden, I conservatively marked a few things which
seem safely hidable.

 - $outer fields and accessors
 - classes whose classfile has the jvm Synthetic attribute
   (not to be confused with the SYNTHETIC flag)

I leave additional choices to those who have a better idea how
this will materialize (i.e. IDE guys.)

It is easy to selectively introduce this flag; but the SYNTHETIC flag
is set or checked for in so many places, it is very difficult to alter
the logic around it (either by setting it less, or checking for HIDDEN
only) with much confidence. So right now HIDDEN is only used to help
ACC_SYNTHETIC make it into bytecode - it is only set in conjunction with
SYNTHETIC, and it doesn't help anyone hide from the typechecker.

Review by @dragos, @odersky.
Collection of updates to SIP-14 (scala.concurrent)

Developed by Viktor Klang and Havoc Pennington

- add Promise.isCompleted

- add Future.successful and Future.failed

- add ExecutionContextExecutor and ExecutionContextExecutorService for Java interop

- remove defaultExecutionContext as default parameter value from promise and future

- add ExecutionContext.Implicits.global which must be explicitly imported, rather
  than the previous always-available value for the implicit EC

- remove currentExecutionContext, since it could create bugs by being
  out of sync with the implicit ExecutionContext

- remove Future task batching (_taskStack) and Future.releaseStack

    This optimization should instead be implemented either in
    a specific thread pool or in a specific ExecutionContext.
    Some pools or ExecutionContexts may not want or need it.
    In this patch, the defaultExecutionContext does not
    keep the batching optimization. Whether it should
    have it should perhaps be determined through benchmarking.

- move internalBlockingCall to BlockContext and remove currentExecutionContext

    In this patch, BlockContext must be implemented by Thread.currentThread,
    so the thread pool is the only place you can add custom hooks
    to be run when blocking.
    We implement BlockContext for the default ForkJoinWorkerThread in terms of
    ForkJoinPool.ManagedBlocker.

- add public BlockContext.current and BlockContext.withBlockContext

    These allow an ExecutionContext or other code to override
    the BlockContext for the current thread. With this
    API, the BlockContext is customizable without
    creating a new pool of threads.

    BlockContext.current is needed to obtain the previous
    BlockContext before you push, so you can "chain up" to
    it if desired.

    BlockContext.withBlockContext is used to override the context
    for a given piece of code.

- move isFutureThrowable into impl.Future

- add implicitNotFound to ExecutionContext

- remove default global EC from future {} and promise {}

- add ExecutionContext.global for explicit use of the global default EC,
  replaces defaultExecutionContext

- add a timeout to scala-concurrent-tck tests that block on SyncVar
  (so tests time out rather than hang)

- insert blocking{} calls into concurrent tck to fix deadlocking

- add NonFatal.apply and tests for NonFatal

- add OnCompleteRunnable marker trait

    This would allow an ExecutionContext to distinguish a Runnable originating
    from Future.onComplete (all callbacks on Future end up going through
    onComplete).

- rename ListenerRunnable to CallbackRunnable and use for KeptPromise too
  Just adds some clarity and consistency.
Merge pull request #857 from vjovanov/master

Removing the non-deterministic actor migration test.
Merge pull request #856 from havocp/sip14-execution-changes

Collection of updates to SIP-14 (scala.concurrent)
bandaid in GenASM for SI-6049
Merge pull request #840 from jsuereth/fix/newstarr-with-source

STARR now includes source
Revert "GenASM: pipeline disk-write with building of classfiles"

This reverts commit 5d12fa4b791e73d5c99a0e145d28cbaba12823d2.
Fixed very bad build.xml issue and quick.bin missing ASM.
Merge pull request #860 from jsuereth/fix/critical-build-fixins

Fixed very bad build.xml issue and quick.bin missing ASM.