rigidbody: Don't use icons for constraint type

We don't have proper icons yet.

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@54404 954f8c5b-7b00-dc11-b283-0030488c597c
rigidbody: Relink constraints when duplicating objects

This will preserve constraint <-> rigid body realationships so
constraint setups aren't broken after duplication.

Based on a patch by Brandon Hechinger (jaggz), thanks.

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@54405 954f8c5b-7b00-dc11-b283-0030488c597c
rigidbody: Fix force field changes not invalidating cache

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@54406 954f8c5b-7b00-dc11-b283-0030488c597c
rigidbody: Add missing updates for rigidbody operators

Fixes cache not being invalidated when using change collision shape and
calculate mass operators.

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@54407 954f8c5b-7b00-dc11-b283-0030488c597c