bugfix for negative addresses
added ALF meta instruction
improved logging and error reporting
implemented div/compare operations
implemented IOC operation as NOP
added DoubleWord class for ra/rx mixed operations
added bug fixing tests
fixed various low-level  bugs
improved logging
now main is interactive
successfully run 500 Primes
bugfix for local references
added IO functions (only printer emulation works)
added memory access validation
named registers, for debugging purposes