alt-tab toggles between active editor and tree view

src/app/keymaps/tree-view.coffee

@@ -1,9 +1,13 @@
+window.keymap.bindKeys '.editor'
+  'alt-tab': 'tree-view:focus'
+
 window.keymap.bindKeys '.tree-view'
   'right': 'tree-view:expand-directory'
   'left': 'tree-view:collapse-directory'
   'enter': 'tree-view:open-selected-entry'
   'm': 'tree-view:move'
   'a': 'tree-view:add'
+  'alt-tab': 'tree-view:unfocus'
 
 window.keymap.bindKeys '.move-dialog .mini.editor, .add-dialog .mini.editor'
   'enter': 'tree-view:confirm'

src/extensions/tree-view/tree-view.coffee

@@ -34,6 +34,10 @@ class TreeView extends View
     @on 'tree-view:directory-change', => @selectActiveFile()
     @rootView.on 'active-editor-path-change', => @selectActiveFile()
 
+    @on 'tree-view:unfocus', => @rootView.activeEditor().focus()
+    @rootView.on 'tree-view:focus', => this.focus()
+
+
   deactivate: ->
     @root.unwatchEntries()