added view for checked ast

new view in gui for checked ast(yet not implemented in semantic analyser),
instantiated attributes map in ASTNodeImpl
changing background in textbased gui elements
Merge branch 'gui'

merge branch gui(new view for checked ast) into master
+ Disabled superfluous print outs
+ Removed some @Ignore
+ Changed test cases according to changes in ASTFactory.addWhile(...)
+ Completed M3MatricMultTest
Merge branch 'master' into parser