Numeric ops

[aziz-mu]

This PR Implements some of the functions from issue #942 . Specifically, it implements for integers:

• bitwise and (&)
• bitwise OR (|)
• bit shift left (<<)
• bit shift right (>>)
  New tests are included as well. I'll do factorial in another PR as it requires additional parser support

[andyfengHKU]

I have an additional comment on factorial. If factorial can be supported by simply modifying

oC_UnaryAddOrSubtractExpression 
    : ( MINUS SP? )? oC_StringListNullOperatorExpression ;

to

oC_UnaryAddSubtractOrFactorialExpression
    : ( MINUS | FACTORIAL SP? )? oC_StringListNullOperatorExpression ;

then let's do it. Otherwise we don't need this syntax sugar for factorial given there is already a factorial function exists in the code base.

My concern is on the antlr4 side. Antlr4's performance will degrade as we add more and more rules.

[aziz-mu]

Turns out adding factorial syntax was a lot easier than I thought, so I added it as part of this PR too.