POD, test tweaks

	modified:   lib/Weather/OpenWeatherMap.pm
	modified:   lib/Weather/OpenWeatherMap/Error.pm
	modified:   t/error.t
Mock UA for testing, OpenWeatherMap.pm test

	modified:   lib/Weather/OpenWeatherMap.pm
	modified:   lib/Weather/OpenWeatherMap/Test.pm
	modified:   t/openweathermap.t