Apply clang-format-all.sh using the _clang-format file through all the cpp/.h files.
make sure not to apply it to certain serialization structures, since some parser expects the * as part of the name, instead of type.
This commit contains no other changes aside from adding and applying clang-format-all.sh
add sphere2.urdf
move btSpatialAlgebra into LinearMath
remove some warnings, introduce BT_ZERO, BT_ONE, BT_HALF as defines for 0.f/0., 1.f/1., 0.5f/0.5 respectively