[BREAKING](#21)Change the cache option from a cache instance to a config object
[BREAKING](#21)Change the cache option from a cache instance to a config object

The options merging and cloning has some problems with the way cache
clients are created, so rather than hope the merging and cloning
works we can just instanciate a cache instance because the interface is
all we care about. The dirty work is done with the engine

node-tastypie/tastypie