translations.pri: List languages sorted like 'ls' output
Files with relative paths can now be opened from command line

Closes #1109
[bash/zsh completion] Complete also filenames and directories

See #1109
[shell completions] Rename and edit readme
[shell completions] Fix markdown syntax in README.md
[shell completions] Bash completion is installed into /usr/share/...
Fixed showing "//" as receiver in Thunderbird form  "Send page/link ..." actions

Instead of empty receiver address, just one space %20 is used.
[Fix] Url with only query is valid too

mailto:?subject=foo should be treated as valid url too

Closes #1112
Merge branch 'master' into ComboTabBar