Memcache nova

* Added consul service for memcache.
 * Memcache should be a central service in order to use it to store tokens and to use multiple consoleauths. So adding a consul service for that.
 * added better test for memcached.
 *Added spec tests
* Added memcached based caching for nova controllers
 * This is required to support multiple nova consoleauth nodes.
* Fixed issue on configuring private_address/public_address on cp nodes
* Fail/error the nova config on runtime using a type rather than fail using fail function during compile time which was causing a situation where puppet never executes on nova controllers.
* include ntp on ceph.pp to avoid spec test failures