adding ability to attach to the active pane

adding ability to attach to the active pane instead of the
workspaceView which solves issue #9 about split panes

![screenshot 2014-05-13 13 41 36](https://cloud.githubusercontent.com/assets/145288/2957162/27cb32d4-da9b-11e3-9453-7e4aaf9acedb.png)