Remove context and extensions, make client API also use the core.
Make a new pw_remote object that keeps connections with remote
instances.
Remove introspection API, it's just as easy to connect to the registry
and get updates like that.
Expand the protocol a little to make it useful for making listeners
and connections.
Move protocol specific connection to the module. Make some new
convenience methods.
Make a factory to create nodes from spa objects
Add an example of a local pipeline displaying a v4l2 source.
Rework the node and port API so that other implementations can be used
than the spa_node. The plan is to morph this into the stream and
context API.
Rework the graph API a little so that init + add is separated.
Make real spa_graph nodes and ports and schedule those. This makes
it possible to add explicit tee and mixers in the real graph.
Rework the way we add and remove ports and nodes from the graph.
Remove confusing pw_port_link and merge core with pw_link_new()
Move scheduling in separate files, add some more graph-schedulers.
Replace the AsyncDone event with an explicit done callback in the node
to signal completion of an async operation.
Pass read and write fd together with the transport
Make a default logger and mapper in a .h file to be used by examples
Remove logger and mapper from libs
Make method to set the default mapper for the debug methods
