Fixes #3246 Deadlock when multicast and tcp are enabled simultanious.

XML Config Builder now rejects this
When a member starts, there is validation if JoinConfig is valid
Improved JoinConfig.verify test
Added correct test annotations on the JoinConfigTest
Merge pull request #3333 from pveentjer/fix/3.x/3246-multicasttcp-nodefreeze

Fixes #3246 Deadlock when multicast and tcp are enabled simultanious.