Rename variables

mysql_host -> database_host
mysql_user -> database_user
mysql_password -> database_password

Please also see the following pull requests:
https://github.com/hpcloud-mon/ansible-monasca-thresh/pull/19
https://github.com/hpcloud-mon/ansible-monasca-api/pull/43
https://github.com/hpcloud-mon/ansible-monasca-notification/pull/23

Change-Id: I1d18b8290cceefe339e1b5260804ff241a8a5a98

host_vars/mini-mon

@@ -8,7 +8,7 @@ kafka_hosts: "{{mini_mon}}:9092"
 kafka_listen_address: "{{mini_mon}}"
 kafka_heap_opts: "-Xmx256m"
 keystone_host: "{{devstack}}"
-mysql_host: "{{mini_mon}}"
+database_host: "{{mini_mon}}"
 nimbus_host: "{{mini_mon}}"
 percona_package: percona-xtradb-cluster-56
 smtp_host: localhost

mini-mon.yml

@@ -57,21 +57,21 @@
     - {role: monasca-api,
        influxdb_user: mon_api,
        influxdb_password: password,
-       mysql_user: monapi,
-       mysql_password: password,
+       database_user: monapi,
+       database_password: password,
        tags: [api]}
     - {role: monasca-persister,
        influxdb_user: mon_persister,
        influxdb_password: password,
        tags: [persister]}
     - {role: monasca-notification,
-       mysql_user: notification,
-       mysql_password: password,
+       database_user: notification,
+       database_password: password,
        tags: [notification]}
     - {role: storm, storm_nimbus_enabled: true, storm_supervisor_enabled: true, tags: [storm]}
     - {role: monasca-thresh,
-       mysql_user: thresh,
-       mysql_password: password,
+       database_user: thresh,
+       database_password: password,
        tags: [thresh]}
     - {role: monasca-agent, tags: [agent]}