Added types and cleaned up the code. Made it so Memcached, Redis, and other classes are now passed through the constructor.
Refactored the package to support the future cache PSR.
Updated router for cache changes.
Type checker fixes.
Quick changes.
Combine the expires and cache file objects in FileSystemStorage.
Merge from master.
Updated caching tests in the view package.
Updated readme.
Use DateTime for expirations.
Merge pull request #36 from milesj/cache-package

Cache Package
Merge branch 'master' into io-package
Removed Writer::append(). Added a new ResourceMap type.
Correctly type hint the bundle interface.