Tests for each instruction and some bug fixes to those instructions.
Complain better in SyntaxError constructor.
More tests and changes to accomodate those tests/fix bugs.
More work on tests; added coverage.
Added test for MemoryVerifier.
Added tests for TTY view.
Memory loading should round number of words up, not down.
Remove lots of debug logging.
Performance improvement.

- Memory undo state now uses a list rather than a dictionary.
  Dictionaries are apparently pathologically slow... sometimes.
Implemented all the numbers in the schematic view.
Removed some dead code.
Merge branch 'bsim'
Merge branch 'master' of github-mattpf:terman/6.004x