these are pretty final now
New check-test op forms: is-not, satisfies-not, is%(eq), is-not%(eq).
Also, added basic test cases for all check-test ops.
Emacs: pyret mode support for new keywords: is-not, satisfies-not
Merge branch 'master' of https://github.com/brownplt/pyret-lang
Merge remote-tracking branch 'origin/master' into torepr-pp.  Also fixing a small bug in equality that made one test fail; with this fix, all tests pass again.

Conflicts:
	src/arr/trove/ast.arr
	src/js/base/ffi-helpers.js