Display count of resources in header on top of resource tables.
Removes spinner after initializing TinyMCE instance.
Refactors Alchemy.windows.js with Coffescript.

- Converts all options from overlay windows into objects.
- Documents the methods.
- Puts TrashWindow into its own namespace.
Only display current site languages in language_switcher helper.
Extends upgrader with notice about render_picture_editor refactoring.
Uses published_at for page#cache_key timestamp. Closes #366
Removes the published_at attribute and uses only the page#id for cache_key. Refs #366
Ensures that from_current_site scopes return at least default site.
Removes "upgrade to sites" from Upgrader. The seeder handles this.

The Seeder will now assign existing languages to the default Site instead of always creating a new one.
Adds a downsizing example for preprocess_image_resize config option.
Respect upscale parameter for picture rendering.
Prevents image upscaling in pictures controller per default.

Only allow upscaling if `:upsample` parameter is set to true.
Merge branch 'master' of https://github.com/magiclabs/alchemy_cms
change dragonfly for amazon s3 support