Removed all System.out.println. Introduced logger where there before were sysouts. Set logging up correctly with a console logger (no more dupe logging statements). Added 'transient' on the logger for Expression class. Refactored one package in test (others come later - or they will be removed).
Merge branch 'master' of https://github.com/tkok/GSD-code
Organized imports.
Minor fix.