CiviCRM 5.13.0 release

CiviCRM version 5.13.0 is now out and ready to download. Please note that the next CiviCRM security release is expected on 15th May. It is going to be a point release of 5.13. 
 
One of big improvements in 5.13.0 is being able to use mysql lock handling for 5.7 MySQL sites - see this PR for more details.
 

RELEASE NOTES: