start on restricting argument to generated PushInt instructions

that is, issue #5. updated the compiler and proved a general theorem
about the push int code generator, but haven't fixed the proofs where
that theorem now needs to be used.
update compile_varref_thm for PushAnyInt
fix prim1_to_bc_thm
finish updating bytecodeProofTheory
Merge remote-tracking branch 'origin/master' into PushAnyInt
add PushAnyInt stuff to compiler compset
add support for translating integer negate
prove side conditions resulting from PushAnyInt