Make font-patcher Python 3 compatible.
Fedora's fontforge modules only work on Python 3. The small changes in
this patch make font-patcher work on Python 3 so I can run the script on
Fedora (26 at least, I don't know about older versions)
Update DejaVu README from upstream
Kill DejaVu/Powerline in favor of original DejaVu fonts
Update font-linux screenshot with new code points, fixes #138
Move fontforge screenshots from wiki to repo