Make sure your resources are properly trollied

The plan

• load scripts asynchronously
• utilise localStorage for caching if available
• preserve loading order
• support synchronous loading
• support "immediate" scripts (they execute immediately as loaded irrespective of the order)
• provide callback for script loaded
• provide callback for script loaded that fires if script has already been loaded before
• support for CSS
• evict from localStorage based on version - partial make sure it evicts non versioned as well
• evict from localStorage based on insertion time when no version
• provide error callback
• allow people to add their own loaders based on content type
• documentation
• tests
• have lots of tea