added joint names filter parameter to joint state controller

This patch introduces a "joints" parameter that overwrites the joint names selection of the joint state controller.
It enables to run multiple joint state controllers with different publish rates and can be useful to harmonize bevahiour of simulation and real robots.
Defaults to publishing all joint names if no parameter is given.

Please use a more descriptive name for `restricted`. Eg. `use_custom_joints`. I you can think of something briefer yet descriptive of the purpose, even better.