[Paddings & Alignement]

- Fix paddings on snCollisionResult and snIConstraint.
- Remove alignement for snPhysicMaterial class.
EPA Triangle

Fix padding. Going from 80 bytes to 64.
Sweep Manager Alignement

Fix alignement from 96 to :
- 80 with SN_DEBUGGER on
- 64 with SN_DEBUGGER off.
Terrain Description

Fix warning signed/unsigned mismatch.
EPA Triangle

Remove the simplex from the constructor as it's not used.
HeightMap

Fix warning signed/unsigned mismatch.