Fix for BUG#22511: IM does not remove angel-pid-file on clean shutdown
Fix for BUG#22511: IM does not remove angel-pid-file on clean shutdown


server-tools/instance-manager/mysqlmanager.cc:
  Delete IM-angel pid file on exit.

flynn1973/mariadb-aix,ollie314/server,natsys/mariadb_10.2,ollie314/server,flynn1973/mariadb-aix,davidl-zend/zenddbi,natsys/mariadb_10.2,natsys/mariadb_10.2,flynn1973/mariadb-aix,flynn1973/mariadb-aix,davidl-zend/zenddbi,natsys/mariadb_10.2,davidl-zend/zenddbi,natsys/mariadb_10.2,davidl-zend/zenddbi,natsys/mariadb_10.2,ollie314/server,ollie314/server,natsys/mariadb_10.2,slanterns/server,flynn1973/mariadb-aix,davidl-zend/zenddbi,flynn1973/mariadb-aix,davidl-zend/zenddbi,flynn1973/mariadb-aix,flynn1973/mariadb-aix,natsys/mariadb_10.2,davidl-zend/zenddbi,davidl-zend/zenddbi,flynn1973/mariadb-aix,natsys/mariadb_10.2,flynn1973/mariadb-aix,ollie314/server,natsys/mariadb_10.2,ollie314/server,ollie314/server,davidl-zend/zenddbi,davidl-zend/zenddbi,ollie314/server,ollie314/server,davidl-zend/zenddbi,ollie314/server,ollie314/server,flynn1973/mariadb-aix,natsys/mariadb_10.2