find object based on hsv color histogram of the pointcloud

Find object based on color histogram.
You can choose the bin size and what kind of color parameter to use (hue, saturation, value and joint of hue and saturation)

The likelihood is calculated from bhattacharyya coefficient.

The green box on the right image is the selected point cloud.
The colored pointcloud on the left image is the result of the estimation.

![screenshot_from_2014-06-26 16 07 55](https://cloud.githubusercontent.com/assets/40454/3395613/2ac15008-fd01-11e3-8b78-b5961c1be8e3.png)