Update trove meeting time

During the trove project update last week, it was decided to change
the meeting time to 10am CT[1], which is 1500 UTC. To better
accomodate contributors working in or near the GMT timezone.

This was discussed and confirmed in the meeting this week[2].

[1] https://youtu.be/g8tKXn_Axhs?t=23m50s
[2] http://eavesdrop.openstack.org/meetings/trove/2017/trove.2017-05-17-18.00.log.html

Change-Id: I1ff3ec0da3b99f783c8d0867b667e272346f45ab

meetings/trove-dbaas-team-meeting.yaml

@@ -2,11 +2,11 @@ project:  Trove (DBaaS) Team Meeting
 meeting_id: trove
 agenda_url: https://wiki.openstack.org/wiki/Meetings/TroveMeeting
 schedule:
-  - time:       '1800'
+  - time:       '1500'
     day:        Wednesday
     irc:        openstack-meeting-alt
     frequency:  weekly
-    start_date: 20160106
+    start_date: 20170524
 chair:  Amrith Kumar (amrith), Mariam John(johnma), Peter Stachowski (peterstac), Craig Vyvial (cp16net), Nikhil Manchanda (slicknik)
 description:  >
   Want to add an agenda item? Please append your item to the upcoming weekly