Fix gcc warnings for non-autoconf 32bit Linux build

as suggested by magnum
Wordlist.c: Fix clang compiler warning (or even bug) in restore_state()
caused by commit 0dcff5d8
wordlist.c: let all regex specific code depend on #if HAVE_REXGEN

to avoid compiler warnings.
The code did get a bit uglier and harder to read, though.
Merge pull request #614 from frank-dittrich/bleeding-jumbo

Some small fixes