Cleaned up statement implementations a bit to move to always returning completions.
Cleaned up for impl a bit
Working to move more logic into encapsulated computations.
Fixed EnvironmentReference set always setting current environment
Working on cleaning up reference apis to be a bit more sane
Added iref semantics
More work on references.
Continued to clean up reference api
Fixed try for case where finally returns a completion
Initial ugly work on handling the case where caught throw yields the previous value before the throw.
Throw completion returned through suc path instead of error path.
Begin moving computation operations that are not really semantics to new operations modules.
Moved over rest of files for now
More splitting of files.
semantics.js now simply aggregator, split off program and value semantics.
Removed declar from expression file.
Small cleanup