"image info" and "flavor info" implementations are trivial and are
implemented by these methods:
* snf_get_flavor
* snf_get_info

"server info" is implemented by this method:
* snf_get_server
but also requires the following side implementations:
* snf_get_server_volume_links (volume attachments)
* snf_get_server_net_attachments (server nics)

Modifications in the json response template had to be applied in
in snf_get_server and snf_get_server_net_attachments to achieve
OpenStack compatibility