Added UnusedMethodDetector with tests.
Moved functionality to check if method was truely called from UnusedMethodDetector to CallGraph.
Merge branch 'unusedmethod'
Changed structure to support IDetector interface.
Added UnusedMethodIssue.
Added MethodInfo to call graph to support getting the method context.
Added method context and source file.
Added source file of the MethodNode.
Added getParseTreeSourceFile() to get a SourceFile object.
Create issues for unused methods.
Fixed that graph was not saved.
Added deleting an unused method.
Added unused method support.
Determine if a method is called is happening if a method call is found instead of checking this if the call graph is completely created.