Use MMAllocMisc, define prototype on our own.

Not all backends for Dylan provide run-time.h.
Also, when using MPS, one should use MMAllocMisc for this sort of
data rather than primitive_allocate().
Merge pull request #8 from waywardmonkeys/no-run-time-h

Use MMAllocMisc, define prototype on our own.
Merge pull request #9 from promovicz/rename-to-interface

Renamed libraries and modules command-system -> command-interface
Progress on new completion system
Keep a reference to completions in options
Some enhancements to completion subleties

This makes implicit completion aware of the now-present information
on whether the completion is truly "complete". We only limit implicit
completion for cases where the completion is declared "exhaustive".
XXX Wonky utility functions
Adjusted bash completion to new completion model
Bugfix in previous.
Made file completion suck a teensy bit less

No thanks to locators.
Conditionalized autospacing in certain cases