Fix exception in Maniphest task ID filtering

Summary:
Ref T2632. When the user enters task IDs, we filter them to allow the user to write `T123` or `task 123` to mean `123`. This filtering is latin-centric and silly, and cuases an exception when accessing, e.g,, `/maniphest/view/custom/?tasks=~`.

Instead of stripping a select few nondigits, strip all nondigits.

Test Plan: Hit `/maniphest/view/custom/?tasks=~`, no exception.

Reviewers: AnhNhan, chad, vrana

Reviewed By: chad

CC: aran

Maniphest Tasks: T2632

Differential Revision: https://secure.phabricator.com/D5193

src/applications/maniphest/controller/ManiphestTaskListController.php

@@ -731,7 +731,7 @@ final class ManiphestTaskListController extends ManiphestController {
       $numeric_task_ids = array();
 
       foreach ($task_ids as $task_id) {
-        $task_id = preg_replace('/[a-zA-Z]+/', '', $task_id);
+        $task_id = preg_replace('/[^\d]+/', '', $task_id);
         if (!empty($task_id)) {
           $numeric_task_ids[] = $task_id;
         }