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/integration/NVIDIA/premake4.lua

@@ -0,0 +1,35 @@
+	
+	hasCL = findOpenCL_NVIDIA()
+	
+	if (hasCL) then
+
+		project "OpenCL_integration_NVIDIA"
+
+		initOpenCL_NVIDIA()
+	
+		language "C++"
+				
+		kind "ConsoleApp"
+		targetdir "../../../bin"
+
+		initOpenGL()
+		initGlut()
+		initGlew()
+
+
+			includedirs {
+		"../../../rendering/BulletMath",
+		"../../primitives"
+		}
+		
+		files {
+			"../main.cpp",
+			"../../basic_initialize/btOpenCLUtils.cpp",
+			"../../basic_initialize/btOpenCLUtils.h",
+			"../../opengl_interop/btOpenCLGLInteropBuffer.cpp",
+			"../../opengl_interop/btOpenCLGLInteropBuffer.h",
+			"../../opengl_interop/btStopwatch.cpp",
+			"../../opengl_interop/btStopwatch.h"
+		}
+		
+	end