Added few innodb_* options

  Added possibility to set:
    -  innodb_io_capacity
    -  innodb_io_capacity_max
    -  innodb_flush_neighbors

Change-Id: I5038366282eb9cecbda17180ba43231d79c052ed
Related-Prod: PROD-36083
diff --git a/metadata/service/slave/cluster.yml b/metadata/service/slave/cluster.yml
index 991db2a..166c235 100644
--- a/metadata/service/slave/cluster.yml
+++ b/metadata/service/slave/cluster.yml
@@ -18,6 +18,9 @@
     galera_xtrabackup_parallel: 0
     galera_error_log_enabled: true
     galera_error_log_path: /var/log/mysql/error.log
+    galera_innodb_io_capacity: 500
+    galera_innodb_io_capacity_max: 2000
+    galera_innodb_flush_neighbors: 1
   galera:
     slave:
       enabled: true
@@ -47,6 +50,9 @@
       xtrabackup_parallel: ${_param:galera_xtrabackup_parallel}
       error_log_enabled: ${_param:galera_error_log_enabled}
       error_log_path: ${_param:galera_error_log_path}
+      innodb_io_capacity: ${_param:galera_innodb_io_capacity}
+      innodb_io_capacity_max: ${_param:galera_innodb_io_capacity_max}
+      innodb_flush_neighbors: ${_param:galera_innodb_flush_neighbors}
   mysql:
     server:
       users: