Minor fix in documentation of ScalaCompletions class.
Restore compatibility with IDE plugins.

The new field in `ScalaSyntaxClass` broke source and binary compatibility with
both play2 and worksheet. This breaks my flow, as I want to be using the latest
master builds while working on play2.
Fix delayedInit debugger test for 2.11.

The compilation scheme for delayedInit has changed in 2.11. This commit updates
the test (the implementation didn't need any changes).
Merge pull request #378 from dragos/issue/fix-2.11-test

Fix delayedInit debugger test for 2.11.
Merge pull request #377 from dragos/refactor/restore-plugin-compatibility

Restore compatibility with IDE plugins.
Merge pull request #376 from aldenml/doc-scalacompletions-fix

Minor fix in documentation of ScalaCompletions class