Formatting cleanup in grammar
Some more grammar cleanup (these weren't doing anything)
Implement += and flesh out expression handling some more
String indexing and method calls
Pass and break
Inject false and true into a constant scope
Implement unary minus, do some misc code cleanup, and start a (non-working) implementation of array slices
Some beginnings on Coral unit tests. Not very functional yet.
Simplify overly complex LValue deref handling
Get array slices working
Add a dictionaries test and fix one uncovered bug
Add another bit to the eventual parser test
Add refs for the existing Coral tests
Metal calls should also deref LValues
Add string.join and <string>.split, and update test runs not to include const values