Fixed transcoding of multi-part/multi-media items.

Fixes #1041
Added a easy way to synthesise server with just one Connection
Don't call CServerManager::FindByHostAndPort from PlexFile.

Related to #1042
Don't call CPlexServerManager::FindByHostAndPort in playMedia command

Related to #1042
Simplify ManualServerManager a lot.
Remove CPlexServerManager::FindByHostAndPort

Fixes to #1042
Don't crash when not using GDM.
Added 1.0.10 release notes.