905ea10272
- DU< had same comparison order bug as D< (comparing d2-hi < d1-hi instead of d1-hi < d2-hi). Fixed with SWAP U<. - 2VARIABLE and 2CONSTANT were handled as special tokens but not registered in the dictionary, so they couldn't be called from compiled code (e.g., : CD4 2VARIABLE ;). Added pending codes 9/10.