Convert most demos to GLES 2

Also fix Viewport error in 3D scaling demo, add an icon to Multiplayer Bomber, and rename BPM sync files.

loading/autoload/project.godot

@@ -34,3 +34,7 @@ singletons=[  ]
 [memory]
 
 multithread/thread_rid_pool_prealloc=60
+
+[rendering]
+
+quality/driver/driver_name="GLES2"

loading/background_load/project.godot

@@ -103,3 +103,7 @@ ui_end={
 "events": [ Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":0,"alt":false,"shift":false,"control":false,"meta":false,"command":false,"pressed":false,"scancode":16777230,"unicode":0,"echo":false,"script":null)
  ]
 }
+
+[rendering]
+
+quality/driver/driver_name="GLES2"

loading/scene_changer/project.godot

@@ -30,3 +30,7 @@ window/stretch/aspect="expand"
 [gdnative]
 
 singletons=[  ]
+
+[rendering]
+
+quality/driver/driver_name="GLES2"

loading/threads/project.godot

@@ -30,3 +30,7 @@ singletons=[  ]
 [memory]
 
 multithread/thread_rid_pool_prealloc=60
+
+[rendering]
+
+quality/driver/driver_name="GLES2"