add fileOpenDialog and enable loading of urdf from GUI
(will add .bullet file support soon)
Uses native Windows (getFileOpenFileName) and Mac OSX NSOpenPanel,
on Linux using pipe popen to zenity)
CMake: remove CMAKE_INSTALL_PREFIX from CMakeLists.txt it is automagically used
See also https://github.com/bulletphysics/bullet3/pull/227
remove pthread from OpenGL/GlutStuff.cpp for now (it breaks CMake build)
fix support for dynamic loading of X11 functions, after adding XRaiseWindow
./premake4_linux64 --force_dlopen_x11 gmake
Merge remote-tracking branch 'bp/master'
Merge pull request #229 from erwincoumans/master

add fileOpenDialog selector (Win/Mac/Linux), CMake remote CMAKE_INSTALL_PREFIX,fix support for dynamic loading of X11 functions