Add fixed_key parameter
Add fixed_key parameter

fixed_key is a generated HEX string
This value will be used for encrypting/decrypting
volumes created by Cinder (cinder-volume) and
accesing it with Nova (nova-compute)

Partial-Bug: #1420849

Change-Id: If039678b6c69d54ebdd203fc2ed247b3cca103cf

zhaochao/fuel-web,nebril/fuel-web,nebril/fuel-web,zhaochao/fuel-web,huntxu/fuel-web,prmtl/fuel-web,eayunstack/fuel-web,nebril/fuel-web,eayunstack/fuel-web,nebril/fuel-web,stackforge/fuel-web,huntxu/fuel-web,stackforge/fuel-web,prmtl/fuel-web,zhaochao/fuel-web,zhaochao/fuel-web,prmtl/fuel-web,stackforge/fuel-web,SmartInfrastructures/fuel-web-dev,eayunstack/fuel-web,SmartInfrastructures/fuel-web-dev,SmartInfrastructures/fuel-web-dev,eayunstack/fuel-web,huntxu/fuel-web,nebril/fuel-web,eayunstack/fuel-web,zhaochao/fuel-web,huntxu/fuel-web,prmtl/fuel-web,SmartInfrastructures/fuel-web-dev,SmartInfrastructures/fuel-web-dev,prmtl/fuel-web,huntxu/fuel-web