[Merge] lp:~phablet-team/messaging-framework/leave-and-dissolve-session-adapt into lp:messaging-framework

[Roberto Mier Escandón ]

The proposal to merge lp:~phablet-team/messaging-framework/leave-and-dissolve-session-adapt into lp:messaging-framework has been updated.

Commit Message changed to:

Added on_group_quit() callback to announce we have left the group

NOTE: This MR goes along with https://code.launchpad.net/~ningbo-team/ningbo/leave-and-dissolve-session/+merge/292828

For more details, see:
https://code.launchpad.net/~phablet-team/messaging-framework/leave-and-dissolve-session-adapt/+merge/292826
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Your team Ubuntu Phablet Team is requested to review the proposed merge of lp:~phablet-team/messaging-framework/leave-and-dissolve-session-adapt into lp:messaging-framework.