Just name mail 'Mail', it's that simple; Upddate changelog

CHANGELOG

@@ -1,6 +1,7 @@
 CHANGELOG Roundcube Webmail
 ===========================
 
+- Fixed new_user_identity plugin to work with updated rcube_ldap class (#1487994)
 - Plugin API: added folder_delete and folder_rename hooks
 - Added possibility to undo last contact delete operation
 - Fix sorting of contact groups after group create (#1487747)

program/localization/en_GB/labels.inc

@@ -24,7 +24,7 @@ $labels['password'] = 'Password';
 $labels['server'] = 'Server';
 $labels['login'] = 'Login';
 $labels['logout'] = 'Logout';
-$labels['mail'] = 'Email';
+$labels['mail'] = 'Mail';
 $labels['settings'] = 'Personal Settings';
 $labels['addressbook'] = 'Address Book';
 $labels['inbox'] = 'Inbox';

program/localization/en_US/labels.inc

@@ -28,7 +28,7 @@ $labels['login']     = 'Login';
 
 // taskbar
 $labels['logout']   = 'Logout';
-$labels['mail']     = 'Email';
+$labels['mail']     = 'Mail';
 $labels['settings'] = 'Settings';
 $labels['addressbook'] = 'Address Book';