Check #1 part a

1) Added checks for Add, Minus, Multiply, Divide
2) Updated Arithmetic and its sub Ops
3) Updated Binary Op
4) Added doBinaryExpr in MyParser
Check #1 added more subparts

Added checks to:
1) Mod
2) Relations
3) Equality
Add/Update ModOp.java
Merge branch 'mito'

Conflicts:
	check1.rc
	src/ArithmeticOp.java
	src/ModOp.java
	src/MyParser.java
	src/parser.java
	src/rc.cup
	src/sym.java
Additional Updates
Committing MyParser
Updated MyParser and UnaryOp