SolverMerger: it is now possible to add odesolvers implemented in plugins to the collision group mechanism.

git-svn-id: svn://scm.gforge.inria.fr/svnroot/sofa/trunk@9743 b7f1a160-662a-0410-a6d8-bea165342f16
adding BaseLinearSolver, a base class without API, just to identify linear solvers for the collision group mechanism. Other solvers that does not follow the LinearSolver API can now be handled in the collision group mechanism.
(By the way, it could even be called BaseNumericalSolver)

git-svn-id: svn://scm.gforge.inria.fr/svnroot/sofa/trunk@9744 b7f1a160-662a-0410-a6d8-bea165342f16
Compliant: including collision group mechanism for compliant solvers. TODO: handle every cases...

git-svn-id: svn://scm.gforge.inria.fr/svnroot/sofa/trunk@9745 b7f1a160-662a-0410-a6d8-bea165342f16
Flexible: renaming FrameMass to DeformableFrameMass

git-svn-id: svn://scm.gforge.inria.fr/svnroot/sofa/trunk@9746 b7f1a160-662a-0410-a6d8-bea165342f16
Compliant: more flexible (and more compliant) mechanism to merge Compliant's linear solvers implemented outside of the Compliant plugin.

git-svn-id: svn://scm.gforge.inria.fr/svnroot/sofa/trunk@9747 b7f1a160-662a-0410-a6d8-bea165342f16
fix compilation on windows

git-svn-id: svn://scm.gforge.inria.fr/svnroot/sofa/trunk@9748 b7f1a160-662a-0410-a6d8-bea165342f16