1. Modified UpdateData to be split into two parts. Regular UpdateData that updates data values that are required by the simulator, and UpdateExtraData that contains items that the user can specify that they want. Instead of using a flag for this before I added a list to the simulation of objects where this method should be called. This is now done after all parts have been stepped because I ran into a bug where it was trying to get the force applied to a part before the child muscle parts had applied their forces.

2. Fixed an issue when an old V1 project was converted directly to Bullet it was defaulting the mass to 1Kg because there was no mass in the file to load. I changed this so that in the GUI object it defaulted to -1 to signal the simulation to calculate the mass instead of loading it. The GUI then reloaded the mass during initialization.

3. I believe there is still a bug or inconsistency in the way the bullet forces are being applied. I left some test code in there.
Found a bug in the OsgLine code for bullet. Bullet applyForce method assumes that the coordinate of force application are in world coordinates relative to the COM of the part where it is being applied. Vortex was different. For the rigid body it used the actual global coordinates, and for VsForceStimulus it used a method that took the local coordinates. I modified OsgLine to calculate the correct position required for Bullet. This has not been tested though.
Commmented out some debug statements in VsLine.
Setup AnimatTesting to run Bullet tests.