Implement most of the administrative UI for approval queues

Summary:
Nothing fancy here, just:

  - UI to show users needing approval.
  - "Approve" and "Disable" actions.
  - Send "Approved" email on approve.
  - "Approve" edit + log operations.
  - "Wait for Approval" state for users who need approval.

There's still no natural way for users to end up not-approved -- you have to write directly to the database.

Test Plan: See screenshots.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Differential Revision: https://secure.phabricator.com/D7573

src/applications/people/controller/PhabricatorPeopleApproveController.php

@@ -0,0 +1,66 @@
+<?php
+
+final class PhabricatorPeopleApproveController
+  extends PhabricatorPeopleController {
+
+  private $id;
+
+  public function willProcessRequest(array $data) {
+    $this->id = idx($data, 'id');
+  }
+
+  public function processRequest() {
+
+    $request = $this->getRequest();
+    $admin = $request->getUser();
+
+    $user = id(new PhabricatorPeopleQuery())
+      ->setViewer($admin)
+      ->withIDs(array($this->id))
+      ->executeOne();
+    if (!$user) {
+      return new Aphront404Response();
+    }
+
+    $done_uri = $this->getApplicationURI('query/approval/');
+
+    if ($request->isFormPost()) {
+      id(new PhabricatorUserEditor())
+        ->setActor($admin)
+        ->approveUser($user, true);
+
+      $title = pht(
+        'Phabricator Account "%s" Approved',
+        $user->getUsername(),
+        $admin->getUsername());
+
+      $body = pht(
+        "Your Phabricator account (%s) has been approved by %s. You can ".
+        "login here:\n\n  %s\n\n",
+        $user->getUsername(),
+        $admin->getUsername(),
+        PhabricatorEnv::getProductionURI('/'));
+
+      $mail = id(new PhabricatorMetaMTAMail())
+        ->addTos(array($user->getPHID()))
+        ->addCCs(array($admin->getPHID()))
+        ->setSubject('[Phabricator] '.$title)
+        ->setBody($body)
+        ->saveAndSend();
+
+      return id(new AphrontRedirectResponse())->setURI($done_uri);
+    }
+
+    $dialog = id(new AphrontDialogView())
+      ->setUser($admin)
+      ->setTitle(pht('Confirm Approval'))
+      ->appendChild(
+        pht(
+          'Allow %s to access this Phabricator install?',
+          phutil_tag('strong', array(), $user->getUsername())))
+      ->addCancelButton($done_uri)
+      ->addSubmitButton(pht('Approve Account'));
+
+    return id(new AphrontDialogResponse())->setDialog($dialog);
+  }
+}