Make a couple of the jit tests work with modules.
add RPython compatibility
add regression test for r_dict
add struct's inheritance
Tests for predicates on impersonators
Remove module lookup hack for chaperone/impersonator operations on procedures
Forgot about unsafe vector operations for chaperones
Move definition of equal? to stdlib to avoid writing it in Python
More tests
add struct tests for copying, update and subtypes
Comment out strangely-failing assert.
Make unsafe vector code not do bounds checks.
Testing bubble sort better.
Record module environment with module references so that they don't go through an indirection.

Really, this should be fixed by passing the top-level env
around in the env_structure so this gets set at assignment
conversion time, but that would be more work.
add assertions that the index in the unsafe version can't be negative
Merge branch 'master' into cache-envs

Conflicts:
	pycket/interpreter.py
	pycket/test/jit.py
	pycket/test/test_ast.py
	pycket/values.py
Avoid duplicate bounds checks.
Add some new string functions
Add strings to equal?
Fix naming issue in equal? function