STS user impersonation - EUCA-8496

EUCA-8496
Add token service action for use with user console - EUCA-8502

A new eucalyptus specific GetAccessToken action is added to the tokens
service. Tokens issued by this action are suitable for use with IAM
actions.

EUCA-8502
STS user impersonation, fix action - EUCA-8496

EUCA-8496
Merge remote-tracking branch 'origin/dev/sjones/EUCA-8502' into testing
Consistent formatting prior to code commit for EUCA-8095
Deleted repetitive volume detachment logic on NC
EUCA-8134: reconfigure haproxy with ssl termination
  1) server certificate's ARN is delivered to servo VMs, which will fetch it using iam:downloadservercertificate
  2) for each new LB, we create an unique role and instance profile.
  3) for each new HTTPS/SSL listener, we put a new IAM policy that
     allows the role to download the server cert. This way, we ensure the server-cert
     will be accessible by a servo VM that's only for a specific loadbalancer.
     This security measure is in addition to using EUARE's token for proving that
     the requester is any servo VM.
  4) Euare's authorization check is slightly modified to accomodate the specifics of server-cert