Add a Conference_Host flag to CallState
Add a Conference_Host flag to CallState

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=29086
Reviewed-by: Simon McVittie <2b470b34502dbf3ba4bcc04ea7e64f4e0e104f33@collabora.co.uk>

TelepathyIM/telepathy-spec,freedesktop-unofficial-mirror/telepathy__telepathy-spec