Updated the iris core

- processor.* is now core.*
- The main from processor.c is now in iris.c
- Updated mkfile
Renamed core.* to iris.*

Updated the mkfile as well.

I did this to make the core once again simple
Added ifthenelsejump form to structure

This form makes it possible to compress two conditions into a single
instruction. This form makes it possible to save instructions in cases where if
else conditions occur.
Implemented ifthenelse form
Updated the architecture documentation
Reduced the number of combine bits

The four bits assigned to the combine bits now number only three. This is done
to recover some space (as they are going to be unused anyway).
Arch documentation now describes compare

This completes the base documentation
Deleted the mkfile
iris now uses a Makefile