Add "Move to new message" option when selecting posts on topic admin wrench

[techAPJ (Arpit Jalan)]

This feature is now implemented. Details here:

Move posts to private conversation

This feature is now available via: https://github.com/discourse/discourse/commit/70fdc1036598df09d236e013fea7fcf750c7363f When moving posts from a topic there will be three options. Move to … New Topic Existing Topic New Message When moving posts from a PM there will be two options. Move to … New Message Existing Message