Add tmux package and common dotfiles deployment

dotfiles/common/.tmux/plugins/tmux-continuum/CONTRIBUTING.md

@@ -0,0 +1,15 @@
+### Contributing
+
+Code contributions are welcome!
+
+If you wanna contribute a bigger feature, please open a github issue so we can
+discuss it together first.
+
+### Reporting a bug
+
+If you find a bug please report it in the issues. When reporting a bug please
+attach:
+- a file symlinked to `~/.tmux/resurrect/last`.
+- your `.tmux.conf`
+- if you're getting an error paste it to a [gist](https://gist.github.com/) and
+  link it in the issue