docs: add basic documentation

chore: update environment description

chore: pass PROGRAM argument to objdump make target

tests: fix ram and control_unit tests to match newest architecture

fix: make Makefile work with memory load, write files

chore: update nixpkgs

tests: fix simple cpu test to use memory.dump and doesnt wait for ebreak

tests: add more custom tests

chore: extend memory

chore: pass in full trace file instead of program name

tests: add register dump, printing

fix: shift left only by 5 bits

fix: lui, force rs1 zero, always add

tests: compile only once, copy proram, memory files to correct locations

chore: add python cache to gitignore

feat: add support for official tests

chore: add python to flake

tests: add python test environment for custom tests

chore: load gcd parameters from memory

chore: remove first unused register