MSAL Python 0.5.0

UPDATE at 2019-8-13: There was a bug affecting all previous MSAL Python versions until it is now fixed in MSAL Python 0.6.1. We recommend customer to upgrade to MSAL Python 0.6.1 or above.

• Supports SubjectName/Issuer (SNI) authentication. (#60, #71)
• Supports customizable client claims for confidential client, by a new client_claims parameter documented here. (#67, #68)
• Other minor patch(es). (#69)