Allow albums to have two (or more) dots in the name. Fixes #1897.

modules/gallery/models/item.php

@@ -806,7 +806,7 @@ class Item_Model_Core extends ORM_MPTT {
 
     // Do not accept files with double extensions, they can cause problems on some
     // versions of Apache.
-    if (substr_count($this->name, ".") > 1) {
+    if (!$this->is_album() && substr_count($this->name, ".") > 1) {
       $v->add_error("name", "illegal_data_file_extension");
     }
 

modules/gallery/tests/Item_Model_Test.php

@@ -520,4 +520,10 @@ class Item_Model_Test extends Gallery_Unit_Test_Case {
       $this->assert_true(false, "Shouldn't get here");
     }
   }
+
+  public function albums_can_have_two_dots_in_name_test() {
+    $album = test::random_album_unsaved(item::root());
+    $album->name = $album->name . ".foo.bar";
+    $album->save();
+  }
 }