Make a new USE_BUFFERS command to atomically send a buffer array to the
remote client. We can use this to then clean up an old array and go to
the PAUSED state if possible.
Work on formats. Make one structure that can hold all video formats.
Work on pipeline suspend and resume.
Add jpeg support to v4l2.
Work on enum_formats with a filter in v4l2.
Keep state variable to enumerate things. This allows us to remove the
expectation that the same index will give the same item.
Use a new rectangle type for video size. When enumerating sizes, this
allows us to specify relations between width and height more easily.
Remove the struct and bytes type, they are like pointer.
Add filter to enum_formats to speed up enumerations.
