OdeSolverStatic: set velocities/accelerations to zero

In static mode, the time is out of the equation, we are only looking for an equilibrium, so we should not have any velocities nor accelerations.
So we set them both to zero instead of approximating them with a discrete time step...
Coding standard + improve documentation
OdeSolverStatic improve documentation and variable naming in UnitTest
Rename all OdeSolver (prefix by 'OdeSolver')

- prefix all OdeSolver derived classes with 'OdeSolver'
- match class name with filename
- match internal name with class name
Fix coding standard (spacing) in all OdeSolver derived classes
Add static solvers support to Physics::DeformableRep + update UnitTest