Fix model defaults

[etaoxing]

Category

• New feature
• Bugfix
• Breaking change
• Refactoring
• Documentation
• Other (please explain)

Description

Fix model defaults such that they are assigned within ModelBuilder functions instead of in function defs. This allows for users to modify ModelBuilder.default_* values. Otherwise, even when users set new values, the functions in ModelBuilder would use old values.

Also fix Model.soft_contact_max to return 0 when soft_contact_particle is None.

Changelog

• Update Model.soft_contact_max property
• Update ModelBuilder's add_joint_revolute(), add_joint_prismatic(), add_triangle(), add_edge(), add_cloth_grid(), add_cloth_mesh(), add_particle_grid(), add_soft_grid(), add_soft_mesh(), set_ground_plane()

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[eric-heiden]

Thank you for your contributions, @etaoxing! Your changes look good to me.