SliderJoint support in the OpenSim parser

[tjstienstra]

Is your feature request related to a problem? Please describe.
When trying to import the Tug of War osim model I got a segmentation error, due to the SliderJoint not being supported by the osim parser (was using v0.8.34 in python 3.8). Sidenote: got a segmentation error instead of the error message that the joint was not yet implemented.

Describe the solution you'd like

• Support the opensim SliderJoint with the dart/dynamics/PrismaticJoint
• Normal error message instead of segmentation error when trying to parse a unsupported joint.

Describe alternatives you've considered
None

Additional context
Would expect that implementing the SliderJoint (PrismaticJoint) is quite easy, since I expect that the syntax is basically the same as the already support PinJoint ('RevoluteJoint`).