Implementing a basic cloud auto scaling policy

[sskhiri]

Use case

Assumption:The open nebula infrastructure is deployed and RoQ VM are available.
When the auto scaling processors detects that we need to scale up a queue by creating new exchanges, the scaling policy must be called.
In this scaling policy when there is no available Exchange slots on existing running RoQ hosts, the system must use the open nebula endpoint to send the create VM command.

Dependencies

This task depends on the issue #100 .

[sskhiri]

The basic auto scaling configuration for OpenNebula or Amazon

We have to implement 2 features:

• The slot management at the Scaling policy level
• The cloud scaling policy in a cloud controller such as Scalr, RIghtScale, or cloudwatch

Idealy, the RoQ Scaling policy should manage the host slots and must be able to notify the cloud controller when a new VM must be created.