Rank based take/drop/slice.

Tree navigation based on node rank is faster than using compare
method. rank is simply count(tree.left) + 1.
SI-6374 Scala reflection now supports Java CRTP

Translation of Java types to Scala types has previously been
existentionalizing raw types of ParameterizedType arguments.

As shown in https://issues.scala-lang.org/browse/SI-6374
this leads to cyclic reference errors. If you wonder about the
mechanism of the error, take a look at the comments to the
aforementioned issue - there's a detailed explanation.

However calling rawToExistential is completely unnecessary, because
existential parameters of the results are immediately discarded,
and only prefix and symbol are used later on (which means that
existential extrapolation performed by rawToExistential also doesn't
after the result).

Finding out this was tough, but the rest was a piece of cake.
Getting rid of the call to rawToExistential when translating ParameterizedType
fixed the problem.
Reflection no longer produces faux existentials

Because of using plain ExistentialType factory of a case class
typeToScala sometimes returned existentials with empty quantifieds.

Changing ExistentialType to newExistentialType, which simply returns
the underlying types if params are empty, fixed the problem.
SI-6374 Reflection now works for anns with enum fields

Enum members are static and, therefore, they need to be looked up in
classSymbol(<enum>).companionModule, rather than in classSymbol(<enum>).
refactors java reflection tests

All javac-produced artifacts are now placed into test/files/lib
SI-6287 fixes synthetic symbol clashes in toolbox

Apparently synthetic classes like $anonfun$1 have two properties:
1) Their names are generated using a counter unique to a compilation unit
2) After flatten they levitate to the nearest enclosing package

As a result if we use an empty package to wrap toolbox codegen,
then this package will soon be overflown by $anonfun$1 symbols, because:
1) New codegen session = new compilation unit = new counter which starts at 0
2) New codegen session = new anon funs that end up as children of empty package

Creating a freshly named package for each codegen session fixed the problem.
Now anonfuns from different sessions end up with different parents.
Removed many @inline annotations and final modifiers.

It is my belief that these @inlines and finals landed between
unhelpful and harmful. I am sure this will be disputed in some
cases. It's too much and too difficult to measure except in the
aggregate unless we have specific @inline sites to discuss.
I don't know upon whom the burden of proof lies.  I think we
should err on the side given here, since there is no evidence
of any consistent rationale being applied and it is easy to
verify the negative impact scala compiler inlining can have on
hotspot's far more sophisticated inlining.
improved reflection documentation
clarify caveats of App trait
test case closes SI-5770
Retain Ordering in drop/take/slice signatures.

Addresses code review feedback by @axel22.
Add RedBlackTree tests for take/drop/slice.

Addresses review feedback by axel22.
Merge pull request #1324 from scalamacros/ticket/6374

Scala reflection now supports Java CRTP
Merge pull request #1341 from rkuhn/document-App-RK

clarify caveats of App trait
Merge pull request #1327 from scalamacros/ticket/6287

SI-6287 fixes synthetic symbol clashes in toolbox
Fixes SI-6354: improved error messages for Dynamic signature mismatches.

If an error occurs afer a Dynamic rewriting, augment the error message
with the rewritten tree and a hint to check the Dynamic method
signature.
improved/fixed reflection docs based on comments
Merge pull request #1335 from cvogt/topic/reflection-scaladoc

improved reflection documentation
SI-6390 removes Trees#ArrayValue from the API

Introduced by uncurry - therefore it can be seen
neither by macros, nor by runtime reflection.

Despite never being pickled, ArrayValue is supported by unpickler
so I couldn't move it exclusively to scala-compiler.jar.

Figuring out the mysterious reason for pickling ArrayValue is left
to future work.
Merge pull request #1343 from namin/dynamic-sig

Fixes SI-6354: improved error messages for Dynamic signature mismatches.