Fix expected response in tests

-Updates 'environment' and 'notify' tests so that they will pass if the
URL in the response body contains either http or https as the protocol
-Update 'invalid-api-key' test so that it checks that the error contains
401 instead of a 422
Add ability to specify request options for notify and trackDeployment
Update documentation
Merge pull request #46 from jeffjo/jeffjo/add-request-options

Jeffjo/add request options