This adds a very basic implementation of a list of namespace+eventType
combinations that each node is interested in by just running the
glob operations in for-loops. Some parallelization is possible, but
not enabled by default.

It only wires up keeping track of what the local event bus is interested
in for now (but doesn't use it yet to filter messages).

…ions; local node is probably better anyway

Co-authored-by: Tom Proctor <tomhjp@users.noreply.github.com>