Merge branch 'VRFS-18'

manifest

@@ -3,3 +3,4 @@ users.sql
 sessions_api_v1.sql
 users_v1.sql
 p2p.sql
+collapse_participants.sql

up/collapse_participants.sql

@@ -0,0 +1,4 @@
+DROP TABLE music_session_clients;
+
+ALTER TABLE connections ADD COLUMN music_session_id VARCHAR(64) REFERENCES music_sessions(id) ON DELETE SET NULL; 
+ALTER TABLE connections ADD COLUMN ip_address VARCHAR(64);