Updated tests for node-whois

I added a "test" target to the Makefile and updated the npm package to use the "make test" command for testing. I found about half of the tests failed for me. I noticed many reset connections, so I added a few more WHOIS hosts to distribute the tests across and reduce the likelihood your IP address would becoming restricted. I also noticed case-sentivity issues with matching, so I lowercase the data before matching. Lastly, I updated the test to honor specified WHOIS server, to check that the response came from the specified server.