Add dedicated 8 and 16 bit data types
Use Word/DoubleWord internally in Memory
Use Word/DoubleWord internally in Registers
Make DoubleWord incrementable, update usage in Registers
Fix comment
Add bitmask testing
Add bitmask setting and unsetting
Add logical AND
Use new data types in Registers, Memory and I8080 (almost exclusively)
Use new and()
Update or() and xor()
Update invert()
Remove unused method
Make ALU methods use Word/DoubleWord
Migrate incExtern and decExtern
Migrate Decoder's interface
Add DoubleWord add() and subtract()
Add missing equals() and hashCode()
Use Words for CPU I/O
Use Words internally