ADD User cache
Merge branch 'develop' of github.com:telefonicaid/fiware-orion-pep into task/IOTCORE-233_Keystone_Authentication_Cache
ADD Project cache
ADD Role retrieval cache
ADD Configurable TTLs
FIX Remove unused config property
FIX Default TTL for cache items
ADD Refactor extract roles to clarify function
ADD Refactor retrieve user function to clarify it
ADD Refactor retrieve roles for clarification
ADD Refactor retrieve roles to hold incoming requests
ADD Extract the chache and hold mechanism to an external function
ADD Extract the chache and hold mechanism to an external function
ADD Refactor all the Keystone calls to introduce the cache mechanism
Merge pull request #65 from telefonicaid/task/IOTCORE-233_Keystone_Authentication_Cache

Task/iotcore 233 keystone authentication cache