This is a huge change which involves -
* Implementing Folder renames on the FS + Git level
* Implementing the concept of selecting an item in the FoldersListView,
this feature isn't provided by default, and even now I'm not sure if
the semantics which I've implemented are correct. I haven't
implemented multiple folder selection for now.
Related to issue #18
Also, we're now one step closer to allowing notes to be renamed (#23)
Now clicking on a Folder shows all the notes from that folder. You can
even modify the notes, but deleting and adding notes won't work
correctly right now.