WIP: public gallery pagination working
WIP: Styled and linkified gallery
WIP: infinite scrolling on public gallery
Adjust user navigation to work better with new home page

* Restyled user navigation on home page when not logged in
* added GlitterGallery logo to home page
* added explicit dashboard link to user nav (logged in)
* added signed_in and not_signed_in body classes
* Remove h1.logo (center home link) from user nav on home page
* Remove dashboard link on dashboard
Merge branch 'publicgallery' of github.com:EmilyDirsh/GlitterGallery