2.83
add BspDemo.bsp data file 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
remove #include <stdbool.h> it breaks MSVC 2010 enable gtest by default when using premake, added flag without-gtest use gtest ASSERT_EQ( expected_value, actual_value) instead of the reverse, this fixes issue 205 (https://github.com/bulletphysics/bullet3/issues/205)
remove some warnings
add some command-line options --use_jacobi --allow_opencl_cpu
minor cleanup of btgui/demo3 stuff, much more demo cleanup is needed moved some files in btgui/Bullet3AppSupport