Add the GPU rigid body pipeline from https://github.com/erwincoumans/experiments as a Bullet 3.x preview for Bullet 2.80

Extras/RigidBodyGpuPipeline/opencl/opengl_interop/Intel/premake4.lua

@@ -0,0 +1,34 @@
+	
+	hasCL = findOpenCL_Intel()
+	
+	if (hasCL) then
+
+		project "OpenCL_GL_interop_Intel"
+
+		initOpenCL_Intel()
+	
+		language "C++"
+				
+		kind "ConsoleApp"
+		targetdir "../../../bin"
+
+		initOpenGL()
+		initGlut()
+		initGlew()
+
+		includedirs {
+
+		"../../../rendering/BulletMath"
+		}
+		
+		files {
+			"../main.cpp",
+			"../../basic_initialize/btOpenCLUtils.cpp",
+			"../../basic_initialize/btOpenCLUtils.h",
+			"../btOpenCLGLInteropBuffer.cpp",
+			"../btOpenCLGLInteropBuffer.h",
+			"../btStopwatch.cpp",
+			"../btStopwatch.h"
+		}
+		
+	end