Imported Upstream version 0.5.1
Merge tag 'upstream/0.5.1'

Upstream version 0.5.1
Imported Upstream version 0.5.2.1
Merge tag 'upstream/0.5.2.1'

Upstream version 0.5.2.1
Drop 'remove-xdg-open-shebang' patch
Add lintian overrides
Point Vcs headers to debian git repository
Prepare for release