Added procps, hostname, net-tools build_depends

These tools are used during building and testing. I believe that the packages are always installed in Ubuntu machines, but not necessarily on others (ie Fedora).

The deps were added to rosdep for this package in https://github.com/ros/rosdistro/commit/3b969695c28f331557b32244a3a51c8c5f8edf0e