Migrate project membership to edges

Summary:
  - Store project members in edges.
  - Migrate existing members to edge storage.
  - Delete PhabricatorProjectAffiliation.
  - I left the actual underlying data around just in case something goes wrong; we can delete it evenutally.

Test Plan:
  - Ran migration.
  - Created a new project.
  - Joined and left a project.
  - Added and removed project members.
  - Manually called PhabricatorOwnersOwner::loadAffiliatedUserPHIDs() to verify its behavior.

Reviewers: vrana, btrahan

Reviewed By: vrana

CC: aran

Maniphest Tasks: T603

Differential Revision: https://secure.phabricator.com/D3186

src/applications/project/controller/PhabricatorProjectCreateController.php

@@ -35,12 +35,19 @@ final class PhabricatorProjectCreateController
 
       try {
         $xactions = array();
+
         $xaction = new PhabricatorProjectTransaction();
         $xaction->setTransactionType(
           PhabricatorProjectTransactionType::TYPE_NAME);
         $xaction->setNewValue($request->getStr('name'));
         $xactions[] = $xaction;
 
+        $xaction = new PhabricatorProjectTransaction();
+        $xaction->setTransactionType(
+          PhabricatorProjectTransactionType::TYPE_MEMBERS);
+        $xaction->setNewValue(array($user->getPHID()));
+        $xactions[] = $xaction;
+
         $editor = new PhabricatorProjectEditor($project);
         $editor->setUser($user);
         $editor->applyTransactions($xactions);
@@ -56,13 +63,6 @@ final class PhabricatorProjectCreateController
         $profile->setProjectPHID($project->getPHID());
         $profile->save();
 
-        id(new PhabricatorProjectAffiliation())
-          ->setUserPHID($user->getPHID())
-          ->setProjectPHID($project->getPHID())
-          ->setRole('Owner')
-          ->setIsOwner(true)
-          ->save();
-
         if ($request->isAjax()) {
           return id(new AphrontAjaxResponse())
             ->setContent(array(