Add redeploy feature.

ADD:
  - @retry : number of retries.
  - deploy_internal method which will redeploy @retry (max) times if all nodes
aren't deployed.

Add options for redeployments:

ADD:
  - @retries : maximum number of redeployment
  - retry    : deployment option [true|false].
    If true redeployement will be performed until all nodes are deployed (maximum @retries deployments)
  - goal     : deployement option. Set the desired number of deployed nodes. Can be either a ratio of a number of nodes.

M

make internal_deploy private

M

now deploy will not read from the cache (the deployment is allways triggered )
Merge branch 'msimonin-redeploy' into develop

* msimonin-redeploy:
  Add redeploy feature.
merge 0.0.6 -> develop