Let us have a default cache that is not the rails default

We need to split our cacheable machines from the general rails cache, this makes it easier to not have to mokey patch in
the initializers
Merge pull request #9 from Shopify/allow_for_configurable_cache_stores

Let us have a default cache that is not the rails default
Make sure to do a lookup of the cache store, to make sure cache will be set to an instance of ActiveSupport::Cache::Store
Merge pull request #10 from Shopify/fix_cache_store_assumption

Fix cache store assumption
Makes it so we have one and only ONE cache store
Adding test, albeit a weak one
s/thing/store
Merge pull request #11 from Shopify/use_only_one_cache

Makes it so we have one and only ONE cache store
dont insert middleware after BestStandardsSupport

ActionDispatch::BestStandardsSupport is not a thing anymore on rails4, to keep the same order on rails3 and 4 and we instead insert before FixBadAcceptHeader
Merge pull request #13 from Shopify/rails4_middleware

dont insert middleware after BestStandardsSupport
Merge remote-tracking branch 'upstream/master'

Conflicts:
	lib/cacheable/middleware.rb
	test/cacheable_test.rb
	test/middleware_test.rb