upgrade sdk version

Merge pull request #55 from opsgenie/Issue-50-python-sdk

Adding Exception Reason for 502,504 and default exception

Merge pull request #53 from opsgenie/2.1.3

2.1.3

Merge pull request #46 from opsgenie/fix-rate-limiting-bug

only make use of the "took" information in the response, when it's present

Merge pull request #44 from opsgenie/fix-version

fix packageVersion

update urllib3 version to 1.26.2

Upgrade SDK version (2.0.2 -> 2.0.3)

Merge pull request #27 from opsgenie/fix-alert-responders

Fix alert & incident responders

Upgrade SDK version (2.0.0 -> 2.0.1)

Merge pull request #6 from opsgenie/alert-api-extra-sample

Added extra alert api sample