spec: generated TOC with linkable headers

This adds a table of contents to the spec, with a way to get the link of a
header on hover (like on GitHub) and a "return to top" small icon at the
end of each section.

Jekyll generates the H1-level table of contents, and then the current
one is expended using jQuery all the way down to H5 titles. Examples and
H6 headers are ignored.

GitHub's (MIT licensed) octicons are used for nice "link" and "up"
icons.
[backport] SI-7756 Uncripple refchecks in case bodies

In 65340ed4ad2e, parts of RefChecks were disabled when
we traversed into the results of the new pattern matcher.
Similar logic existed for the old pattern matcher, but in
that case the Match / CaseDef nodes still existed in the tree.

The new approach was too broad: important checks no longer
scrutinized the body of cases.

This commit turns the checks back on when it finds the remnants
of a case body, which appears as an application to a label def.

Conflicts:
	src/compiler/scala/tools/nsc/typechecker/RefChecks.scala

Cherry pick of 3df1d77fc984b976efa68098206e801cf3b83a9e
spec: a print stylesheet to remove the TOC when printing
spec: a header that links to the index, with a scala logo

...and a Scala favicon.
Merge pull request #3998 from retronym/backport/7756

[backport] SI-7756 Uncripple refchecks in case bodies
Rename ClassPath.findSourceFile to ClassPath.findClassFile

If you look at the implementation of that method and its usage
its clear that it should have been named `findClassFile` from the
beginning because that's what it does: find a class file and
not a source file.
Get rid of Platform.doLoad method.

Since .NET backend got removed this method is a no-op.
Merge pull request #3999 from mpociecha/classpath-findSourceFile-method-renaming

Rename ClassPath.findSourceFile and delete Platform.doLoad
Merge remote-tracking branch 'origin/2.10.x' into merge/2.10.x-to-2.11.x-20140925
Merge pull request #4002 from retronym/merge/2.10.x-to-2.11.x-20140925

Merge 2.10.x to 2.11.x
Avoid test fragility to changes in Predef

The check file used to contain a stack trace entry from
Predef with a line number. I've made the macro fail
in a different manner that avoids this fragility.
Merge pull request #4006 from retronym/topic/defragility

Avoid test fragility to changes in Predef
Bump timeout in interactive tests from 10s -> 30s.

Seeing too many of these failures on our build servers.

https://scala-webapps.epfl.ch/jenkins/view/2.N.x/job/scala-nightly-auxjvm-2.11.x/148/jdk=jdk8,label=auxjvm/console

This is most likely due to load on the machines.
Cleanup a few flags in test/files/

 * String interpolation isn't Xexperimental anymore

   A few useless Xexperimental flags in tests were left behind by 6917cca,
   after string interpolation was made non-experimental in 983f414.

 * things added under -Xfuture in 2.10 are very much Xpresent now, the
   flag isn't needed anymore.
Better ant / junit interaction

Currently junit test sources are always rebuilt, that's wasteful. The
second dependency on the junit task is there so that the first can be
skipped if sources haven't changed.

Also normalize package names versus location in the `test/junit` folder:
ant isn't very clever when it comes to selectively recompiling tests, so
now editing a test will only cause that one to be recompiled (instead of
~13 files every time).

This makes TDD with junit even faster.
Merge pull request #4007 from retronym/topic/bump-timeout

Bump timeout in interactive tests from 10s -> 30s.
Merge pull request #4009 from gourlaysama/wip/test-flags

Cleanup a few compiler flags in test/files/
Merge pull request #3996 from gourlaysama/wip/spec

spec: generated TOC, with linkable headers and return to top links
SI-8445, SI-6622 test cases, already fixed

They were most likely fixed in #3931 / e3107465c3.

The test case for SI-6622 is taken from Jason's PR #2654. I adjusted
the EnclosingMethod to be `null` in two places in the check file, for
the classes that are owned by fields (not methods).
SI-8868 Fix unpickling of local dummy symbols

These pop up as the owner of symbols in annotation arguments,
such as the ones introduced by the names/defaults desugaring.

The first two test cases here motivate the two patches to Unpicker.

The third requires both fixes, but exploits the problem directly,
without using `@deprecated` and named arguments.

See also 14fa7be / SI-8708 for a recently remedied kindred bug.