Merge branch 'master' into soc-2021-simulation-display

Fix: incorrect force vector locations

While taking the weighted average of vector locations, the net normal
force was being used as the denominator. The correct value to use is
the sum of the magnitudes of all normal forces in the timestep.

Fix error while freeing non primitive collisions shape mesh in rigidbody

The function name was changed in master and caused an error during merge
Now it uses a different function to clear the geometry

Merge branch 'master' into soc-2021-simulation-display

make format

Constraints: visualisation works with kinematic objects

Used the transforms obtained from bullet instead of creating them using
rigidbody/ object data, which only worked for active rigidbodies

Fix memory leak in non primitive collision shape

- The previous commit didn't fix the leak as the mesh data was not being freed every draw call
- Now the mesh is generated during evaluation along with the physics shape.
- The collisions shape draw data mesh is stored in the shared struct, along with the physics references

Fix: Memory leak in non primitive collision shape drawing functions

The ojects containing the non primitive collision shape meshes are stored in
a GSet along with other draw cache shapes and the meshes are freed using these
object pointers

Cleanup: Forces

Fix: Incorrect acceleration. Store velocities of only the last substep, subtract previous velocity from current

Cleanup: Constraints and panels

Constraints:Added functions to get transforms from bullet.
- These should be used in the constraint visualisation functions so that they can be drawn for kinematic objects as well

Fix: Error while storing effectors forces, upto 3 effectors' forces can be stored now.

Fix: Memory issue in store_convex_hull_draw_data: delete the convex hull computer.

Cleanup: collision display: faces of box, cone and cylinder

-Moved code for checking for faces of cone and cylinder to same function as the box
-Cached colliding faces
-Removed unneccesary shader files and used GPU batches instead, for drawing faces

Fix: transform matrix for drawing colliding walls on box shape

Cleanup: Changed the place of non primitive collision shapes functions to draw_cache.c

Fix: Check for colliding faces after stepping through the simulation instead of in the draw engine

-This is a more accurate way to find colliding faces
-Store just the faces instead of the forces

Cleanup: Changed the place of the store_draw_data functions of convex hull and trimesh so that they are called from the draw engine instead.

Cleanup: Constraint linear limits visualisation

-created option to enable/disable fading of walls
-simplified variable names and transform matrices