Swarm 1:1 detect contact left

• Change repo to include /invited
• "Contact left" should be visible in getConversationMembers()
• Add test
• DO client changes

added to epic &19 (closed)

added SprintIn progress label

marked this issue as related to jami-client-qt#475 (closed)

added SprintTo review label and removed SprintIn progress label

mentioned in commit 588890f9

removed SprintTo review label

closed