Move to Twirl for template parsing.

Fixed tests that started failing under 2.11.

* added a strategic `initialize` call before checking `.isAbstractClass`, since
  flags weren’t there yet
* made the stub `play.mvc.Result` a proper public class (default visibility in
  Java is package private). The 2.11 compiler correctly failed those tests.
Updates to be compatible with Scala IDE master

Update to latest version of plugin-profiles to use Scala 2.11.1
Add direct dependency to scala-xml and scala-parser-combinators
Some cleanup ahead of API work.

Unused imports, members, and deprecations.

Didn't touch
TemplateCompilationunitTest/ActionContentAssistProcessorTest, for
which tests fail already anyway.
More linting, bugfixing

Conflicts:
	org.scala-ide.play2/src/org/scalaide/play2/templateeditor/compiler/CompilerUsing.scala