Fix typos

Copied from April 23, 2013 commit on mleibman master
Rollup of Changes from April 23, 2013 by jgoz

This includes the 4 commits on mleibman master labeled:

Add failing test case for inlined filtering
Fix return statement handling when inlining
Add failing test for evaluated returns
Fix inlining for evaluated return statements.
Fix Safari 6 toString() bug

Copied from mleibman master commit on April 30, 2013
jQuery 1.9 destroy fix

Equivalent to May 3, 2013 commit on mleibman master. Modified because we
have headers_0 and headers_1 due to having frozen columns whereas the
original SlickGrid has only a single $headers.
Stop propagation of click event in showMenu

Equivalent to merge pull request #607 on mleibman master on May 17,
2013.