* Fix FindCDD.cmake

* Update README.md

[SMALL IMPROVEMENTS] When solving dual LP switch infeasible and unbounded return flags. In all equilibrium algorithms check whether the number of contacts is 0, in which case return appropriate result (typically infeasible). Improve test_static_equilibrium.

[IMPORTANT CHANGE] Take com as a 3d point rather than a 2d point (this should allow to consider cases in which gravityis not aligned with the z axis in the future).