Final version of second assignment
Working on third assignment
Finished parser
Fixed input - missing 'T's
Fixed grammar bug
Added parsing input file in the interpreter
Fixed bug in retrieving heap size = System.getenv -> System.getProperty
Finished the interpreter with no GC
Fixed interpreter dereference bugs, added pretty printing of statements
Added comments to grammar
Extracted address and memory manipulation to Heap class. 
Added heap traversal.
Completed 3rd assignment