add open_rsvps flag to music_sessions table

db/manifest

@@ -160,4 +160,5 @@ add_timezone_music_session.sql
 scheduled_sessions_2.sql
 scheduled_sessions_3.sql
 scheduled_sessions_cancel_all.sql
-scheduled_sessions_started_at.sql
+scheduled_sessions_started_at.sql
+scheduled_sessions_open_rsvps.sql

db/up/scheduled_sessions_open_rsvps.sql

@@ -0,0 +1 @@
+alter table music_sessions add column open_rsvps boolean not null default false;