More code sharing on media endpoint client comms code
Upgraded to latest ohOs
Dispose of session on watchable thread.
Merge branch 'master' of ssh://core.linn.co.uk/home/git/ohTopology
fix unobserved task exceptions on finalizer
Changed watchable snapshot read.
Merge branch 'master' of core.linn.co.uk:/home/git/ohTopology

Conflicts:
	src/ohTopology/Service.cs
Fixed unit tests.