Do not use dynamic types anymore. The reason is that it's difficult:
- to maintain a shared type database over a network.
- the extra overhead when translating between processes and for
maintaining the translation tables.
- race conditions in translating in RT-threads, this is a problem
because we want to make event streams.
We now have simple enums with types and extension points for all
types. This is also nicer to use in general.
We don't need the mapper anymore or pass strings around as types.
There is a parallel type info system to get more info about ids and
enums and their hierarchy. It can also be used for debugging.
Make explicit links between elements that are used to activate the
next element in the graph.
Make subgraphs a special regular node. Make a link from the
subgraph children to the parent so that the subgraph completes when
all the children completed.
Implement a single process function in plugins
Remove many messages in the client node
Don't unlink the ports of an inactive link because then it might be
possible that the scheduler can't recycle a buffer, instead use
a port flag to mark the ports disabled and change to scheduler to
skip those ports.
