Cleaned up some memory leaks, got rid of gsequence, improved test macro to free memory that it allocated

Conflicts:
	src/hammer.c

All unit tests written except chain and chainl. Removed left_factor_action, we'll handle left-recursion with our caching strategy.

Fixed inconsistent signature of charset parser, registered (still stubbed) unit tests so the build doesn't break :)

Conflicts:
	NOTES