updating zafl.sh and zax to using command line args instead of env for communicating fixed-map addressing

When name of function is specified as entry point for fork server,
pre-insert the fork server init code at the last instruction of the
first basic block in the function.

One version returns a value. STARS is able to find a dead reg.
2nd func if void. STARS finds no dead regs.

The dominator graph algorith completely makes this optimization obsolete.

Instead of the original laf-intel style instrumentation with nested 1
byte compare, we instead instrument each byte separately to provide afl
with hints. We then execute the original cmp/jcc sequence.

Advantages of this method are that we do not have to handle
signed/unsigned comparisons of bytes, nor do we have to deal with having
separate code to handle >=, <=.

Furthermore, we can easily guide AFL towards inducing division by zero,
by doing a compare against 0, i.e., logically add "cmp X, 0" before a "div X" instruction.