In Savanna we have two provisioning engines:
* "savanna" that directly work with nova/neutron/glance/cinder/etc and
we'd like to deprecate it early in Juno release cycle, but it's still
useful due to the fact that it could work ok w/o Heat;
* "heat" engine uses Heat for provisioning of cluster resources, it's
currently under active development and we're ready to make it default
for OpenStack installations with enabled Heat.
Change-Id: I937337b3921e9e51768a118fb4b6bd95962622bd