Patch Set 2: I would prefer that you didn't submit this

- icon for menu entry is missing (green + like "add" in team menu)
- add action is not available on root of the working directory, this would be handy to stage all changes in one action
- add action shouldn't be available on .git folder and all nodes below
- would be nice if multi-selection of multiple files/folders would be also supported
- it works but isn't easy to use as there are no decorators in the repositories view so the status for non-workspace files can only be seen in commit dialog