refocus preview list after performing operation

Allows esc key to exit the command pallete

src/packages/command-panel/src/command-panel-view.coffee

@@ -44,7 +44,6 @@ class CommandPanelView extends View
 
     @command 'tool-panel:unfocus', => @rootView.focus()
     @command 'core:close', => @detach(); false
-    @command 'core:cancel', => @detach(); false
     @command 'core:confirm', => @execute()
     @command 'core:move-up', => @navigateBackwardInHistory()
     @command 'core:move-down', => @navigateForwardInHistory()

src/packages/command-panel/src/preview-list.coffee

@@ -83,7 +83,7 @@ class PreviewList extends ScrollView
     editSession = @rootView.open(operation.getPath())
     bufferRange = operation.execute(editSession)
     editSession.setSelectedBufferRange(bufferRange, autoscroll: true) if bufferRange
-    @rootView.focus()
+    @.focus()
     false
 
   getPathCount: ->