Increase test coverage

[gregseb]

According to our coverage report there are 5 untested lines of code in geomark.py

Those 5 lines reveal three additional tests we should implement...

• Test that attempting to instantiate a Geomark object with no geomark id or geomark url results in the SyntaxError expected on line 19
• Test that attempting to call a geomark get method (info, feature, parts, point, boundingBox) with invalid parameters results in a bad response code as expected on line 200
• Test that the same bad response code is returned when making a post request (create, copy) as expected on line 211