Split the sprite effect out into a separate file

The intention is that it will be easier to add multiple effects
without duplicating the player code.
Install the frame callbacks on init not on set up pipeline

Previously the frame callback on the framebuffer and the new frame
signal from the sink were set up when the pipeline is set up, but I
can't see any reason why they can't be set up on init instead. That
will avoid accidentally setting up multiple callbacks if the pipeline
is set up multiple times.
Bring back the resizing and aspect ratio support

The onscreen window can now be resized and the code to track the
aspect ratio has been copied back in from the original
cogl-basic-video-player example. The effect is now passed the
rectangle to paint in and an orthographic projection is set up. The
point sprite effect is now set up to use the position attribute and
gl_PointCoord rather than gl_FragCoord to work out where in the video
the fragment is.
Add a no-op effect

This adds a no-op effect which just directly draws the sink's pipeline
like the basic video player would. The code to draw the borders is
kept in a separate file so that it could be used by other effects as
well. It's not currently possible to use the effect because the player
always just chooses the first effect.
Include config.h from all the .c files