example of generated code and runtime
arithmetic was separated from arithmtest for interpretator. From generated file was excluded prolog and epilog
f-functions is now working
term in arithmetic program was complicated for test of compiler -> bug in create_object_N functions (in epilog) was found and fixed
first compiler (call-by-value and without GC, but with accurate allocation) was done
Bug in sll_allocate_object was fixed (invalid read beyound of block), test was turned to merge sort
now "make clean -f backend/Makefile" removes autogenerated backend/arithmtest.c for sanity
migration to expr type based on polymorphic variants and parametrized pretty-printers was done