premake4 add option --enable_static_vr_plugin to statically link the VR sync plugin

fix texture caching from previous commit (what happened there?)

examples/pybullet/premake4.lua

@@ -155,6 +155,11 @@ if not _OPTIONS["no-enet"] then
 			"../../examples/MultiThreading/b3Win32ThreadSupport.cpp",
 			"../../examples/MultiThreading/b3ThreadSupportInterface.cpp",
 			}
+			
+if (_OPTIONS["enable_static_plugins"]) then
+		files {"../../examples/SharedMemory/plugins/vrSyncPlugin/vrSyncPlugin.cpp"}
+end
+
 	
 	includedirs {
 		_OPTIONS["python_include_dir"],