fuzzer: a few comment fixups
fuzzer: update the TODO list
testcode: have the assembly work when compiled for x32

hopefully this is the right change, might break regular i686 build
doc: add some info on using ftrace
doc: update ftrace HOWTO
fuzzer: replay_log, changes to have syscall count match that of perf_fuzzer

An attempt to get the system call count to match perf_fuzzer more
closely to add more deterministic replay.

Didn't help when tracking down bugs, but it does make the mmap addresses
almost the same when address space randomization turned off.