This is mostly a simple lexical search+replace but the absence of operator< for
std::weak_ptr<T> leads to some complications, particularly with Evoral::Sequence
and ExportPortChannel.
The process-graph should only be concerned with GraphNodes,
which may or may not be Routes.
This also removes intrinsic connection information from
the graph-node. Connection information is to be kept separate
from the nodes.
When the graph is re-calculated in the background, old information
has to be retained until the new graph becomes active.
Previously *new* information was already stored in the nodes
while the graph is sorted, even though the new graph was not
active.
Paul Davis
Robin Gareus