[CMake][Python] Exposed GeometryModel and GeometryData in python. Little reworked of the headers_variables in the cmakelists

[C++][algo] algorithm updateCollisionGeometry now optionally executes algorithm geometry to compute positions before updating collision objects's positions

[C++][Geom] distances results for computeDistances is not always cleared but replaced by a vector with empty results. The initialization of collision pairs is now  always done in constructor.

[benchmark] Added benchmark of atomic computations with geometry objects such as updating global positions, determine if two objects are in collision, or compute the distance between two objects

[C++][unittest] Added unittest geom.cpp . It tests that we obtain the same results between Pinocchio and hpp-model-urdf for joints and geometry objects positions ; for collisions and distances between two geometry objects

Add unaligned prismatic joint + minor modifications

Fix bug when parsing urdf file model by considering free floating joint

Still cleaning the parser + add tool

[C++] Raise exception when inertia information is missing when build tree with a specific root joint

Functions defined in headers urdf.hpp and jacobian.hpp are set to inline.

The functions should be inlined, otherwise it breaks with the headers
are used in multiple robots mode.

Set default initialization of variables + expose spatial quantities methods + correct bug