Nic::BMC CRUD and proxy operations API

Minor tabs/spaces fix

Permissions setup

Minor typo in apipie docs

Username and password do not need to be shown on GET operations. POST and PUT operations still set the username and password

API power operations routes and tests are changed

Used host model methods as suggested by Dominic, removed LAN operations

Permissions updated according with the new BMC API

Allow API calls to use ipmitool/freeipmi/ipmi standard power operation syntax in addition to Fog's syntax

Removed fixtures specifications and added them to test helper

Flattened attrs username password to avoid keeping symbols in memory