Updated Token.java
Add "^^" as a token
Updated JCTree.java
Add opcode for XOR
Updated JavacParser.java
Pair "^^" (aka CARETCARET) with JCTree.XOR
Updated ByteCodes.java
Add bool_xor and give it an instruction code 260.
Not sure if this might cause problem in the future.
Updated Symtab.java
Added symbol xor for boolean type
Updated Pretty.java
Paired JCTree.XOR with "^^".
Updated TreeInfo.java
Pair JCTree.XOR with "^^"
Updated Tree.java
Add CONDITIONAL_XOR
Updated JmlAttr.java
Add logic for XOR in makeBinary()
Updated JmlTreeUtils.java
Added symbol for XOR
Updated JmlAssertionAdder.java
Added the main logic for XOR
Updated BankingExample.java
Added test code for XOR