* fix topic view selection crash on centerAndReveal
* topic view shortcuts switch to Alt
* change delete behaviour to be smarter
* fetchRelatives recursively handles arrays
* update topic url and Metamaps.Active.Topic when you center
* make heroku work 4 realz
* fetch siblings & center topic keyboard shortcuts - fixes#466
* add keyboard shortcut labels
* update keyboard shortcuts to Ctrl+E, Ctrl+R, and Ctrl+T, and update docs
* zoom extents back to Ctrl+E and use e.preventDefault