Easy install

• Fix a major bug that completely broke the package by not including Debian-specific files (see issue #1 of this repo)
• As part of the fix, steal config file in /etc/default from old gummiboot package
• Bump version number as this version is believed to be fully compatible with systemd-boot v220
• Run gummiboot install after installing package

In retrospective: NOT Final version (!)

Package renaming broke update-gummiboot -- do not use