Add PictogramDisplay to jsk_rviz_plugins

add pictogram(icon) visualization

![b4rlarnccaa6yhx](https://cloud.githubusercontent.com/assets/40454/5334423/fd70fe64-7ed3-11e4-86a2-b1d8694b27b2.png)

movie: https://www.youtube.com/watch?v=AJe1uQupsUE