addition control pkg rule gen: fix

correctly handle extended_default_bitmask and call _splitmask_line().
roverlay 0.3.0

Changes since 0.2.6:
* a lot of fixes/minor enhancements
* build file changes (Makefile/ebuild, helper scripts)
* addition control feature -- regenerate ebuilds by means of replace/revbump
* partial support for running roverlay on non-Gentoo systems (still TODO)