Avoid calls to _vec_load in many cases
Avoid _vec_load for slices of signals
Remove debug output
Only check global pending list when we know a group is on it
Fix read past end of resolved values array
Identify cases where 'LAST_VALUE is never used

Conflicts:
	src/cgen.c
	src/rt/rt.h
Correctly set flags on groups that need 'LAST_VALUE
Avoid call to _vec_load in cgen_call_args