Added open-id Okta integration

[akashvbabu]

• [X ] I have reviewed the contributor guidelines.
• [X ] I have reviewed the code of conduct.
• Per GitHub's Terms of Service, I am aware that I license my
  contribution under the same terms as this project's license, and
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cc: @mbland

[coveralls]

Coverage decreased (-0.2%) to 97.856% when pulling a6d1fd5 on add-okta into 44d01a3 on master.

[coveralls]

Coverage decreased (-0.02%) to 98.071% when pulling 3d7868f on add-okta into 44d01a3 on master.

[coveralls]

Coverage decreased (-0.02%) to 98.071% when pulling ba3d433 on add-okta into 44d01a3 on master.

[coveralls]

Coverage increased (+0.01%) to 98.1% when pulling 2b15c7f on add-okta into 44d01a3 on master.

[mbland]

Just filed #151 to make sure we get around to documenting this!