[#71587328] Adding support for multiple environments. Added dev/prod urls and guzzle options for each environment.
[#71587328] Updating authentication URL to fix broken test. Updating client objects to be explicitly defined for each respective environment in each partner-mapping method.
Merge pull request #3 from zackurben/dev

[#71587328] Fixing the API endpoint URLs for test/prod environments.
6 - Deploy build by Hudson for commit 0893f91973e88ab451e268be809b29f16fc34fa0