Support "not" for in and instanceof

It would be nice if we could use:

• (3 Unable to render embedded object: File (in [2,3,4]) or (3 not in [2,3,4]) instead of () not found.(3 in [2,3,4]))
• also for instanceof

Remarks:

• It doesn't look like a big issue if it's just "!(x in ['x'])", but when the line is longer and more complex and when use together with other parenthesis, skipping one pair of parenthesis means a lot in code clarity. It's just like in SQL, we can add a NOT to NOT LIKE or NOT IN.

Reference: http://www.nabble.com/Groovy-syntax--API-enhancement-td16796998.html#a16810531