Utility Functions to Examples

[Jmeyer1292]

#16 Merged a bunch of changes to reduce duplications in the rct_examples/tools directory. Among these changes were a lot of new utility functions for printing and drawing images, which is fine, but they were added to "core" packages. I want to keep the APIs of rct_ros_tools and rct_image_tools as clean as possible.

So, in summary, all of these utility functions need to be migrated to rct_examples.