Update Evernote note on save using an EventListener...

...instead of binding command to the default save key.

Tried out this fork today and I really like it! I noticed that when I save, though, the evernote note is updated (which is great) but my local copy is not saved (and I would like it to be).

This adds an ``EventListener`` that triggers a call to ``save_evernote_note`` ``on_post_save``.

The only downside I can see is that the status message about the evernote update is overwritten immediately with the status message about saving.