makepkg remix

Archlinux's makepkg, adapted to create .rpm packages using fpm

• TODO: split package support
• TODO: --clean/--cleanbuild
• TODO: eliminate 'fpmx' call (or decide on a better name ;)
• ...more, but it does most of what I need now.

The original verison is not new, but new enough for me. (v4.2.1)