Add styling to Ads and Users pages
Complete gallery index layout

* Changed uploaders to use resize_to_fill option
Style home page and nav
Consolidate custom Sass into one file

* Add title placeholder links on index pages
Fix indentation issue for failing galleries index spec
Fix failing spec after styling home page
Improve home page styles
Add styles to sign in-out forms
Improve form styling to be more consistent
Merge branch 'advanced-styles'
Rename Projects as Ads in nav and in spec for clarity