New implementation of auto save (#58):

saves:

* on editor blur (including split switch)
* on switching files (goto UI etc.)
* on window close
Update, now with `File:Save` command and configurable saveTimeout.
Fixes #278 by adding commands to move splits around:

- Split:Move First
- Split:Move Second
- Split:Move Third
Fixes #256
Implements bartaz' suggestions in
ihttps://github.com/zedapp/zed/commit/4c178f38275d7e6076f7363656fd1c7fd6abfc58
Change saveTimeout to 2s, update whitespace stripper to "change".
Fix undefined exception for sessions like zed::start
Merge pull request #296 from zedapp/new-auto-save

New implementation of auto save
Alternative implementation of #302
Adding "Vagrantfile" to Ruby mode.
Fix ZPM auto-updating packages not in listed in user.json packages key.