Added basic unit test for payflowGateway.cfc.  These unit test will tell you if the gateway is working with paypal.  I have tested these with my own credentials and the test passed.  Someone wanting to test will need to user their credentials (added at the top of the test/payflowTest.cfc) to make the test work.
Merge pull request #2 from penhorwood/master

Payflow unit test from @penhorwood to confirm gateway works as expected for issue #1.