Increase granularity in TimeoutError

[bhargavrpatel]

Summary

Context

Increase the granularity of TimeoutError by introducing child classes, ConnectTimeoutError and ReadTimeoutError to parity the exceptions raised from the requests library.

Changes

• Introduce child classes in braintree.exceptions.http.timeout_error
• Handle ReadTimeouts in braintree.util.handle_exception
• Add integration tests

References

https://github.com/braintree/braintree_python/issues/104

Checklist

• [x] Added changelog entry
• [x] Ran unit tests (nosetests tests/unit)

[bhargavrpatel]

Not sure if the tag needs to be generated on the braintree repo or on my fork.

Also note that I am not entirely sure if we needed Unit tests here given that I only saw an integration test for the timeout behavior.

Finally, do let me know if any changes need to be made. I'd be happy to make them promptly.

Thank you once more.

[bhargavrpatel]

@crookedneighbor I went ahead and rebased the branch with upstream and recreated the branch and applied the changes.