fix EC2 Signature Version 4 calculation, in the case of POST

When calculating the AWS Signature Version 4, in the case of POST,
We need to set the CanonicalQueryString to an empty string. this
follows the implementation of the AWS and boto clients.

Change-Id: Iad4e392119067e246c7b77009da3fef48d251382
Closes-Bug: 1360892
SAML2 federated authentication for ADFS.

Authentication workflow for the Active Directory Federated Services
(ADFS) by Microsoft is different from 'standard' ECP based one.
This plugin allows for authentication and fetching security token with SAML2
assertion inside, sending to the Service Provide and retrieving an
unscoped token.

Change-Id: I588de1967a7fb92c5928686d092895847553923a
Implements: blueprint add-saml2-cli-authentication
Fix a doc_string error

Change-Id: Ib2ab829ed777a4f2fb13ec7426dffef99a4118ab
Merge "fix EC2 Signature Version 4 calculation, in the case of POST"
Merge "Fix a doc_string error"
Merge "SAML2 federated authentication for ADFS."