MEDIUM: Allow configuration of email alerts

This currently does nothing beyond parsing the configuration
and storing in the proxy as there is no implementation of email alerts.

Signed-off-by: Simon Horman <horms@verge.net.au>
diff --git a/include/types/mailers.h b/include/types/mailers.h
index 582bb94..07374a7 100644
--- a/include/types/mailers.h
+++ b/include/types/mailers.h
@@ -23,8 +23,8 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
-#ifndef _TYPES_EMAIL_ALERT_H
-#define _TYPES_EMAIL_ALERT_H
+#ifndef _TYPES_MAILERS_H
+#define _TYPES_MAILERS_H
 
 #include <sys/types.h>
 #include <sys/socket.h>
@@ -61,5 +61,5 @@
 
 extern struct mailers *mailers;
 
-#endif /* _TYPES_EMAIL_ALERT_H */
+#endif /* _TYPES_MAILERS_H */