Add a memory reference helper struct that we can use to track the memory
in buffers and formats.
Remove custom property get and set, the default ones will work fine.
Custom ones are problematic when we want to serialize properties in
formats etc.
Deserialized Formats are now tracked in the memory pool and can be freed
if needed.
Rework things so that we negotiate buffer pools beforehand and only pass
buffer ids around We can then remove the refcount of buffers, events and
commands.
More work on buffer reuse
Use the node state changes to trigger the next step in the configuration
sequence.
Move most of the client-node to a plugin
Do buffer allocation in the port link.
We now only allow per port preallocated buffers. We exchange the index
into the array instead of passing the buffers around. We still use the
refcount to track when a buffer can be reused.
Improve API a little, allow passing the node as the first argument of
the interface call.
Implement alloc_buffer in v4l2 and improve the test.
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.
