Update upload page (beta)

* Add menu button in header chrome
* Make h1's have no margin and add margin to #content_wrapper .content instead
* simplify upload page html (div-itis)
* show message for anonymous users
* move upload button to top of page
* center images in generated list
* remove border on images
* increase thumbnail size to 320 and make constant
* change overlay heading color
* style the call to action at top of the upload dashboard to be fixed to
the top chrome bar

* special page specific:
** only serve js in mf-user-gallery to Special:DonateImage
** add stylesheet for donate page and remove list style on items
** when a list is empty explain why a user should start uploading

Depends on:
https://gerrit.wikimedia.org/r/#/c/45489/

Change-Id: Iddaa736592c4e88d4be18af6a2787f0a12c8fb14
Merge "Update upload page (beta)"