Save under $HOME under a dotfolder

* unsaved edits are then on a persistent
file system
* and 'out of the way' since the folder won't
be visible unless the user is looking for it

Signed-off-by: Ozan Safi <ozan@oscorp.se>
Add unsaved document counter

This is needed in cases where there are
multiple unsaved documents at the same time.

Signed-off-by: Ozan Safi <ozan@oscorp.se>
Merge pull request #10 from ozans/master

Save under $HOME + uniquify filename