Drag-drop file upload.

Summary:
- have files be uploaded by drag+drop instead of browse.
- Files are named by their uploaded filename, the user isn't given a chance to enter a file name. Is this bad?
- Store author PHID now with files
- Allow an ?author=<username> to limit the /files/ list by author.
- If one file is uploaded, the user is taken to its info page.
- If several are uploaded, they are taken to a list of their files.

Test Plan:
- Quickly tested everything and it still worked, I'd recommend some people try this out before it gets committed though. It's a rather huge revision.

Reviewers:
epriestley, Ttech

CC:

Differential Revision: 612

src/applications/files/controller/dropupload/PhabricatorFileDropUploadController.php

@@ -20,6 +20,7 @@ class PhabricatorFileDropUploadController extends PhabricatorFileController {
 
   public function processRequest() {
     $request = $this->getRequest();
+    $user = $request->getUser();
 
     $data = file_get_contents('php://input');
     $name = $request->getStr('name');
@@ -28,6 +29,7 @@ class PhabricatorFileDropUploadController extends PhabricatorFileController {
       $data,
       array(
         'name' => $request->getStr('name'),
+        'authorPHID' => $user->getPHID(),
       ));
 
     $view = new AphrontAttachedFileView();