Include troubleshooting link in SiloUnavailableException

(cherry picked from commit c357114)

Allow liveness config in TestCluster

when creating the client configuration from the cluster config.
Also fixed the deployment name to separate date from time correctly

(cherry picked from commit ffcd3c0)

# Conflicts:
#	test/Tester/MembershipTests/LivenessTests.cs

Change version from 1.2.0 to 1.2.0-beta.