Adds includedir back to templates

This adds includedir to the mysql templates, which allows overriding of
default my.cnf settings. Additionally, /etc/mysql/conf.d is created if it
doesn't already exist to prevent mysql from failing.

Change-Id: I1e051978b2363eaa9fd11abf1b107bd1e9c0edcb
Fixes: bug #1218613

trove/guestagent/manager/mysql_service.py

@@ -679,11 +679,18 @@ class MySqlApp(object):
     def _install_mysql(self):
         """Install mysql server. The current version is 5.5"""
         LOG.debug(_("Installing mysql server"))
+        self._create_mysql_confd_dir()
         packager.pkg_install(self.MYSQL_PACKAGE_VERSION, self.TIME_OUT)
         self.start_mysql()
         LOG.debug(_("Finished installing mysql server"))
         #TODO(rnirmal): Add checks to make sure the package got installed
 
+    def _create_mysql_confd_dir(self):
+        conf_dir = "/etc/mysql/conf.d"
+        LOG.debug("Creating %s" % conf_dir)
+        command = "sudo mkdir -p %s" % conf_dir
+        utils.execute_with_timeout(command)
+
     def _enable_mysql_on_boot(self):
         """
         There is a difference between the init.d mechanism and the upstart

trove/templates/mysql.config.template

@@ -51,3 +51,4 @@ max_allowed_packet = 16M
 [isamchk]
 key_buffer = 16M
 
+!includedir /etc/mysql/conf.d/

trove/templates/percona.config.template

@@ -51,3 +51,4 @@ max_allowed_packet = 16M
 [isamchk]
 key_buffer = 16M
 
+!includedir /etc/mysql/conf.d/