Improve performance of Mark Occurrences

Two simple performance improvements for Mark Occurrences:
- Only update the occurrence annotations if the file is in the active
  editor. Previously, annotations were updated for all open files when
  the caret in the active editor changed.
- Cache the most recently created index so that just browsing a file
  does not create a new index every time the caret position changes.
Add the facility to log incremental compilation.
implemented an extendible quick fix functionality for type mismatch
errors
adjusted proposal message
Merge branch 'master' of git://github.com/scala-ide/scala-ide into quickFixTypeMismatch
Fix 1001222

This bug is introduced with commit 88132af2126baa1a2f32971258a542a5f05de965
Merge pull request #189 from sschaef/issue/semantic-highlighting-exception-fix

Fix 1001222
Merge pull request #186 from SandroGrzicic/master

Fixes #1001219
VirtualFile is added in eclipseProblem at ScalaPresentationCompiler, ScalaHover is changed such that getsInteractiveCompilationUnit instead of CodeAssist
ScalaDamagerRepairer does nothing special, so it is removed. Also codeScanner and scalaCodeScanner was identical, and the part for creating damagerRepairer for them.
Merge pull request #190 from amirsh/master

ScalaHover and PresentationCompiler are changed to be more generalized!
Create the index for a local rename action on the compiler thread.

Fixes #1001231
Merge pull request #191 from misto/issue/local-rename-fails-1001231

Create the index for a local rename action on the compiler thread.
Removed unnecessary bundle version dependencies.
Fixed typo in manifest file.
Revert "Fixed typo in manifest file."

This reverts commit 6215230258b8a500b8d3de2268b64a1622d0d112.
Revert "Removed unnecessary bundle version dependencies."

This reverts commit 8614db5b3c58744fc64ece9281a55a27ca7410f9.
Hyperlinking parts are more generalized, in order to make them work with other plugins.

As a result, some other stuffs are also changed a bit, such as ScalaCompilationUnit and InteractiveCompilationUnit.
Merge pull request #187 from vigdorchik/wip_incr_debug_prop

Add the facility to debug incremental compilation.
Merge pull request #184 from misto/issue/improve-performance-of-mark-occurrences-1001213

Improve performance of Mark Occurrences