More cleanup to SASS (SCSS)
-> Styling 'all listings'
-> Added image URL to form / listing_params / listing attributes
Merge branch 'listings' of github.com:felguerez/top-secret-final-project into listings

Conflicts:
	web/app/controllers/application_controller.rb
	web/app/views/layouts/application.html.erb
	web/app/views/listings/index.html.erb
	web/app/views/listings/show.html.erb
-> Styles individual listings more consistently using 4-column and 2-column layouts
-> Separate homepage layout from the rest of the site's layout
Merge branch 'listings' into development
Merge branch 'listings' of github.com:felguerez/aircycle into development

-> Adds styling for listings
-> Adds image url for "upload"
-> Creates a new template for the homepage
-> Cleans up CSS

Conflicts:
	.gitignore
	lib/air_cycle/entities/listing.rb
	web/app/assets/stylesheets/listings.css.scss