Merge the tip of origin/release/proposed/2019.2.0 into origin/release/2019.2.0

7c3bd95 Update scripts for restoring failed node of Mysql in Galera cluster
1944851 Make safe condition for resource.changes
bcf56fb Call xtrabackup.client.restore to trigger restore
8a9e593 Don't remove mysql data in case of RESTART_CLUSTER
81a0b8c Use pkg.list_pkgs function to determine package state
3870245 Run salt minion restart and do not wait for response
1480c7e Fix isPackageInstalled method when salt return is empty
108da66 Add retries to gnocchi.cleint
ac8bcce Fix getWsrepParameters behavior and Update getGaleraLastShutdownNode and getWsrepParameters
f206346 Add new startFirstNode function
0c4dc2c Add condition for docker pull operation
82d0545 Update git mirror to work with http creds
d8dd2c9 Add restartSaltMinion and upgradePackageAndRestartSaltMinion
fb026be Consider null an error value during mysql verification
f48bb10 Add check for disks i/o utilization to verifyGaleraStatus method
e48741b Split restoreGaleraDb function and add restoreType param support
7c8ac9a Improve error logging for galera recovery pipeline
f89f9b4 Move Galera method to new separate class
0c1e278 Add output of not responding minions to minionsReachable function
ad8e95b Add isPackageInstalled and getIostatValues methods to Salt.groovy class

Change-Id: I161d773461b4f203dd48c39d32645e5aac70acd8