Output request headers when initial test for baseurl fails. Fixes #130

Add timeout to requests.get() calls
Fix pep8 issues
Here's how I was able to get it to work:

```python
def testBadBaseUrlGeneratesExpectedMessage(testdir, webserver):
    STATUS_CODE = 500

    testdir.makepyfile(test_one="""
        import pytest
        @pytest.mark.skip_selenium
        @pytest.mark.nondestructive
        def test_selenium(mozwebqa):
            assert True
    """)
    result = testdir.runpytest('--baseurl=http://localhost:%s/%s/' % (
        webserver.port, STATUS_CODE))
    assert result.ret != 0
    # tracestyle is native by default for hook failures
    result.stdout.fnmatch_lines([
        "*INTERNALERROR*AssertionError*Base URL did not return status code "
        "200 or 401*Response: %s, Headers: {*}*" % STATUS_CODE
    ])
```
Inspiration was taken from https://bitbucket.org/hpk42/pytest/src/b738b91f2dd19157015e2a7bcf8af404126c0998/testing/acceptance_test.py?at=default#cl-42