update parse tests to be suite, and get rid of *-assign for objs

We weren't compiling or desugaring s-dot-assign and s-bracket-assign, because
we took a different route for field extension a while ago.  This commit removes
some dead code for those, as well as cleaning up the parse-tests.rkt file to
use rackunit test-suites.
Merge branch 'master' into unstable
more list support, floor, and commit for sortacle
.
Merge branch 'master' into unstable
args order correct
macro for number primitives; more to be fixed soon
Remove everything to do with seals
remove all seals