Allow use of svg_subsampler in addition to svg2traj executable

Allow use of svg_subsampler instead of svg2traj executable
Allow joint trajectory publishing to be skipped
Adapt to MultiDOFJoinTrajectory msg being moved from moveit_msgs to trajectory_msgs for ROS hydro
Allow for use of curvature-base or homogenous sampling when using svg_subsampler executable
[doc] Made clear that publish_traj is setup for Hydro
Merge pull request #1 from dhood/master

Update to Hydro and allow for different svg-trajectory sampler