Added cache class
Deleted old cache class
Merge branch 'master' into cache

Conflicts:
	composer.json
	src/FelixOnline/Core/App.php
	src/FelixOnline/Core/ArticleManager.php
Merge branch 'master' into cache
Updated get most popular comments query
Split out sql query into its own function in baseDb
Cache sql query results
Get cache using parameters not string
Added cache invalidation stampede protection and only cache most viewed for 30
mins
Clear cache when saving the model
Added cache flag for managers to cache their results
Allow setting of cache expiry when setting cache
Merge branch 'master' into cache

Conflicts:
	src/FelixOnline/Core/ArticleManager.php
Merge pull request #17 from FelixOnline/cache

Cache
Merge branch 'master' into most_commented

Conflicts:
	src/FelixOnline/Core/ArticleManager.php