Fix two minor points UI issues

Summary:
Ref T4427.

  - When points are configured, show them on the task detail page (just a simple property, at least for now).
  - Typecast points better to avoid "joe changed points from 12 to 12." beacuse we compare the stored value (as a string) to the new value (as a double).

Test Plan:
  - Saw points on detail view.
  - Created task with points, then edited it without touching points. No more spurious "changed from 12 to 12" transaction.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T4427

Differential Revision: https://secure.phabricator.com/D15223

src/applications/maniphest/controller/ManiphestTaskDetailController.php

@@ -229,6 +229,15 @@ final class ManiphestTaskDetailController extends ManiphestController {
 
     $view->addProperty(pht('Author'), $author);
 
+    if (ManiphestTaskPoints::getIsEnabled()) {
+      $points = $task->getPoints();
+      if ($points !== null) {
+        $view->addProperty(
+          ManiphestTaskPoints::getPointsLabel(),
+          $task->getPoints());
+      }
+    }
+
     $source = $task->getOriginalEmailSource();
     if ($source) {
       $subject = '[T'.$task->getID().'] '.$task->getTitle();

src/applications/maniphest/editor/ManiphestTransactionEditor.php

@@ -71,7 +71,11 @@ final class ManiphestTransactionEditor
       case ManiphestTransaction::TYPE_COVER_IMAGE:
         return $object->getCoverImageFilePHID();
       case ManiphestTransaction::TYPE_POINTS:
-        return $object->getPoints();
+        $points = $object->getPoints();
+        if ($points !== null) {
+          $points = (double)$points;
+        }
+        return $points;
       case ManiphestTransaction::TYPE_MERGED_INTO:
       case ManiphestTransaction::TYPE_MERGED_FROM:
         return null;