Update changelog for 1.9.18

changelog

+lemonldap-ng (1.9.18) stable; urgency=high
+
+    * #1479: App Category order - Cannot save
+    * #1476: Unescaped left brace generates a warning with Perl-5.28
+    * #1474: OAuth2 token_type is case insensitive
+    * #1514: Aliases not respecting redirect settings
+    * #1494: Manage applications with the lemonldap-ng-cli
+    * #1470: Warning when using CLI to set value which does not exists before
+    * #1469: SMTP timeout breaks Manager configuration save
+
 lemonldap-ng (1.9.17) stable; urgency=high
 
     * #1416: Attribute encoding in CAS responses