Changed methodInvoke and methodNode so that object is pushed on stack after parameters. Fixed a minor issue

- change Test.py to run reachabilityChecking
- basic ASTNode reachCheck
- implemented reachability in: MethodNode, IfNode, WhileNode, ReturnNode
- tiny bit of cleanup (whitespace)

- added fieldType to FieldNode
- added myType to NameNode
- fixed NameNode:checkStatic
- recursively calling disambigName exactly the same as how we do
checkType
- starting NameNode:checkType
- cleaned up Test.py commented code

Added code for Name disambiguation. Fixed CFG for field access. Moved test cases to the correct directory. Not tested yet

- add fields to contain set
- added inherit set
- quick fix for final method getClass in java.lang.Object that was
creating errors