Parenthetizes test nullary methods

One thing that always bugged me in scala-refactoring is that the side-effecting nullary methods had no parentheses.
This fixes it, along with a couple other straightforward issues (e.g. Option warts).
Merge pull request #47 from huitseeker/issue/lints

Parenthetizes test nullary methods
Some of the new tests weren't using the PC.
Fix potential NoSuchElementException on Nil.head

No test included because I had no idea on how to reproduce the behavior
in a test - the exception occurs for me only in a misconfigured compiler
but not in a correctly configured one.
TypeParams added to AddMethod

Type parameters are added for def construction in AddMethod refactoring.
Current implementation limitation:
there is an issue if pass several type params to mkDefDef inside addMethod (inside AddMethod class).
To overcome this issue in the commit all required type parameters names are grouped in one passed typeDef:
val typeDef = new TypeDef(NoMods, newTypeName(typeParameters.mkString(", ")), Nil, EmptyTree)
this typeDef is used while constructing result newDef in mkDefDef.
add generation of unique abstraction name to extractions

Use the scope of the selected code to generate a unique name for the
extracted abstraction.

This moves the responsibility for avoiding name collisions due to
extractions from the IDE to scala-refactoring.
Use 2.11.0 and 2.10.4 for building the published artifacts
AddField refactoring added

Similar to AddMethod, intended for val/var creation.
Current implementation limitation: var printing is implemented with direct
var addition (otherwise var is not printed):
NoSymbol.newVariable(newTermName(s"${nme.VARkw} " + valName))
Run tests that use a selection on the PC thread.
AddField/AddMethod refactoring
Merge pull request #49 from VladimirNik/abstract-members-implementation-api

Added: AddField refactoring, type params to AddMethod
Fix build errors due to detected race conditions
Merge remote-tracking branch 'scala-ide/master' into feature-extractCode

Conflicts:
	org.scala-refactoring.library/src/test/scala/scala/tools/refactoring/tests/common/SelectionDependenciesTest.scala
	org.scala-refactoring.library/src/test/scala/scala/tools/refactoring/tests/common/SelectionPropertiesTest.scala
Merge pull request #51 from Luegg/feature-extractCode

add generation of unique abstraction name to extractions
Prevent double { when adding method to empty trait.
Release version 0.6.2 with the new Extraction Refactorings
Set version to 0.6.3-SNAPSHOT
Prevent double { when adding method to type with abstract super class.
Add missing tests to suite.
fix duplicated arrow when extracting extractors from case statement with body on next line