i18n refactoring: Rename all _() (reserved by gettext) calls to t().

- And refactor printf to our string interpolation / pluralization syntax
- Also, a slight change to the translations_incomings table, using binary(16) instead of char(32) as message key.

core/views/admin_modules.html.php

@@ -1,30 +1,30 @@
 <?php defined("SYSPATH") or die("No direct script access.") ?>
 <div id="gModules">
-  <h1> <?= _("Gallery Modules") ?> </h1>
+  <h1> <?= t("Gallery Modules") ?> </h1>
   <p>
-    <?= _("Power up your Gallery by adding more modules!   Each module provides new cool features.") ?>
+    <?= t("Power up your Gallery by adding more modules!   Each module provides new cool features.") ?>
   </p>
 
   <form method="post" action="<?= url::site("admin/modules/save") ?>">
     <?= access::csrf_form_field() ?>
     <table>
       <tr>
-        <th> <?= _("Installed") ?> </th>
-        <th> <?= _("Name") ?> </th>
-        <th> <?= _("Version") ?> </th>
-        <th> <?= _("Description") ?> </th>
+        <th> <?= t("Installed") ?> </th>
+        <th> <?= t("Name") ?> </th>
+        <th> <?= t("Version") ?> </th>
+        <th> <?= t("Description") ?> </th>
       </tr>
       <? foreach ($available as $module_name => $module_info):  ?>
       <tr>
         <? $data = array("name" => $module_name); ?>
         <? if ($module_info->locked) $data["disabled"] = 1; ?>
         <td> <?= form::checkbox($data, '1', module::is_installed($module_name)) ?> </td>
-        <td> <?= _($module_info->name) ?> </td>
+        <td> <?= t($module_info->name) ?> </td>
         <td> <?= $module_info->version ?> </td>
-        <td> <?= _($module_info->description) ?> </td>
+        <td> <?= t($module_info->description) ?> </td>
       </tr>
       <? endforeach ?>
     </table>
-    <input type="submit" value="<?= _("Update") ?>"/>
+    <input type="submit" value="<?= t("Update") ?>"/>
   </form>
 </div>