Add line to align some element relative to other

![align](https://f.cloud.github.com/assets/1835871/2484157/c4502b16-b109-11e3-8358-b6c8d3b3e52e.gif)
![stem](https://f.cloud.github.com/assets/1835871/2484159/ce367e64-b109-11e3-8695-fb6f96e02c6a.gif)