python-catkin-pkg: updated from 0.1.8 to 0.1.16 (see #99)

The current catkin requires catkin_pkg >= 0.1.12 as indicated in
https://github.com/ros/catkin/blob/groovy-devel/package.xml.
See discussion in #99.

lb: minor tweaking and commit message rewording

Signed-off-by: Víctor Mayoral Vilches <v.mayoralv@gmail.com>