Add a note that "!global" is incompatible with 3.2.

Closes #1121
Bump VERSION to 3.3.0.rc.5
Merge branch 'master' into bleeding-edge

Conflicts:
	VERSION
Fix rubocop.
Fix global assignment deprecation tests.
Merge branch 'master' into bleeding-edge
Rip out the deprecated addition of . to the load path.
Rip out support for passing lists of pairs to map functions.
Rip out deprecated argument names.

Closes #1118
Fix up the 3.3.0 changelog entry for index().
Make local variables shadow globals by default.

Closes #136