Add capsule geometry for collision and visualization.

- note that a capsule collision shape is currently available only in chrono-parallel.
Add 'name' member variable to ChTriangleMeshShape.

This facilitates identifying a mesh in visualization output files (for external rendering, e.g. with POV-Ray)
Merge branch 'develop' of https://github.com/projectchrono/chrono
Merge branch 'master' of https://github.com/jcmadsen/chrono