Interactive scaladoc.

Add interactive scaladoc used when showing the hover and
when presenting scala symbol in the completion popup.

Fix #1000453, Fix #1000210.

Conflicts:
	org.scala-ide.sdt.core.tests/src/scala/tools/eclipse/completion/CompletionTests.scala
	org.scala-ide.sdt.core.tests/src/scala/tools/eclipse/testsetup/TestProjectSetup.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/LocateSymbol.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/ScalaHover.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/ScalaPresentationCompiler.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/ui/ScalaCompletionProposal.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/ui/ScalaCompletionProposalComputer.scala
	pom.xml
Fixes ScaladocGlobalTrait initialization

Packages for 2.11/2.10 source directories

Adds a basic doc test
Corrects PC thread confinement

Corrects Analyzer plugin initialization

Conflicts:
	org.scala-ide.sdt.core.tests/src/scala/tools/eclipse/pc/DocumentationTest.scala
	org.scala-ide.sdt.core.tests/src/scala/tools/eclipse/pc/PresentationCompilerTest.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/LocateSymbol.scala
Fix compilation unit tracking through enclosingPackageClass

Conflicts:
	org.scala-ide.sdt.core.tests/test-workspace/pc_doc/src/varz.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/LocateSymbol.scala

Conflicts:
	org.scala-ide.sdt.core/src/scala/tools/eclipse/ui/ScalaCompletionProposal.scala
Fix hyperlinking thread confinement
add packages & multi-source test cases
relax thread containment

Conflicts:
	org.scala-ide.sdt.core.tests/src/scala/tools/eclipse/completion/CompletionTests.scala
	org.scala-ide.sdt.core/src-2_11/scala/tools/eclipse/ScaladocGlobalCompatibilityTrait.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/LocateSymbol.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/ScalaHover.scala
	org.scala-ide.sdt.core/src/scala/tools/eclipse/ui/ScalaCompletionProposal.scala
Simplified parsedDocComment

Conflicts:
	org.scala-ide.sdt.core/src/scala/tools/eclipse/ui/ScalaCompletionProposal.scala
Constraining the use of getJavaElement
Makes legacy locate available again
more thread confinement, more robust linkChoice
Prevent NSDNHO in LocateSymbol, minor fixes

Should be compatible with scala/scala/pull/2775
Faster enclosing position location for wordPos
Fix for interactive docComment clearing in 2.11

Fixes #1000210, #1000453

finalizes eager site computation

absent return type of getHOverInfo breaks the play2 plugin

FIxing thread confinement in browserInput
more NSDNHO fixing in LocateSymbol

Cosmetics
Avoids memory leak of the inner BrowserInput(html, sym) through the outer pointer
Fix NpE in BrowserInput

Cosmetics

Fix NpE in getHoverInfo
Ports the branch to post-thread-safe-sourceFiles

cosmetics
removing authorship info, obsolete as of #549
Better test case compartmentation
Speed optimizations for findClassFile