Major bug fixes and better SieveVal/Factors gen.

Bug fixes:
-NumSeed was incrementing after the sieve wheel was generated leading to
bad prime generation
-For small TestPrimes, SieveDepth could be =1. Trying to reshape it
resulted in errors

SieveVal now more directly generates based on implicit sieve position.
This removes all composite zeros from SieveVal reducing its size. This
also removes the need for the and() in Factors gen. Faster execution and
smaller mem footprint!