Add an admins only warning module when the usual performance settings are not optimised

YAML
objects: - type: module data: name: admin_performance_warning position: top order: 1 params: nobox: y style: position:fixed;top:0;z-index:1000; custom: | {if $tiki_p_admin eq 'y'} {* warn admins if the performance prefs are not enabled *} {if $prefs.tiki_minify_javascript neq 'y' or $prefs.tiki_minify_css neq 'y' or $prefs.smarty_compilation neq 'never'} {remarksbox type='errors' title="{tr}Admin warning{/tr}" close="n"} {tr}Performance settings not optimised, see <a class="alert-link" href="tiki-admin.php?page=performance">the control panel</a> to correct this{/tr} {/remarksbox} {/if} {/if}