2016-02-10: v1.6.1

• forth: evaluate failed for strings that ended at page boundary
• forth: print error in case include fails
• forth: space optimize of
• forth: moved 2over, 2swap to compat
• cart: made cartridge boot faster
• cart: use Simons' Basic cart type to make $a000-$bfff RAM
• editor: starting without filename now doesn't read from disk
• editor: :w on unnamed buffer now prints "no filename"