added stopwatch to tester
The Int and String primitives now use a class object and chained Get/Set. Functions are no longer bound to "this". These changes provide a 3x speedup on fib_iter_long due to significantly fewer allocations
slua now allows _ in names
tweaks to dyn_obj to put parent in the hashtable
optimized the "parent" access, by storing it in the object instead of the hash table (and used a few guards to make it accessable)
tester fixed up so it only times dynvm itself, it doesn't time the build step anymore