Merge branch 'release/0.0.5'
Merge branch 'release/0.0.6'
Merge branch 'release/0.0.7'
Add tests over oxcart.passes/tree-shake

Not my best cases, but they'll do. The tree shaking emitter is pretty
trivially correct if the reach sets are correct, but they could use
their own tests in future.
Bump version prior to release
Rework priorities again
Merge branch 'release/0.0.8'
Merge tag '0.0.8' into develop

Release 0.0.8

 - Add test cases
 - Add better util functions
 - Add pass management