updated rotunit urdf to be compatible with gazebo

included gazbeo_ros_control plugin and updated transmission interface
setup parameter files for urdf gazebo plugins

adapted rotunit_controller.yaml to use the new effort_controllers/JointVelocityController and adjusted the PID values

included joint_state_controller.yaml to setup the publishing of joint_states for the simulated rotunit at a frequency of 100hz
added gazebo_/ros_control depencies in kurt_base
use generic controller_manager instead of pr2's

adapted the controller manager to respect the changes in the rotunit urdf
added gazebo_/ros_control depencies in kurt_gazebo
set gazebo_topic of the rotunit to be scan360

by convention the rotunit should always publish on scan360 this makes it easier to differentiate
the data coming from the rotunit and other 2d lasers
changed self-filtering in rotunit_filter_chain

since the robot_self_filter is not supported in hydo, self filtering is now based on the laser_filter/LaserScanFootprintFilter which performs a radial point removal around the base_link. in terms of accuracy this is definetly a step back, so we see to get the robot_self_filter working agian.

furthermore the scan topics were changed to be scan360 and scan360_filtered to be better identifiable when rotunit and regular 2d lasers are used side by side
included parameter file for the laser-based self-filtering

currently all points in a radius of 0.5m around the base_link are removed during self-filtering, futhermore a shadow point filtering is applied
fixed dependencies
Merge pull request #6 from hdeeken/hydro

Made rotunit work in gazebo