Add a "assert_memcache_operations" block helper for asserting how many times memcache is hit during the block.
Add a "assert_memcache_operations" block helper for asserting how many
times memcache is hit during the block.

babyvote/identity_cache,Shopify/identity_cache,jeroenj/identity_cache,cuzic/identity_cache,yakovenkodenis/identity_cache,lanrion/identity_cache,midu/identity_cache,Shopify/identity_cache