Use HTTPS urls

Up until now, we were using HTTP urls for the API calls to OpenWeatherMap. Thanks to @Erulezz, we now use the more secure HTTPS versions.

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Fix timezone related issues

This release corrects the use of timezones throughout the project. OpenWeatherMap returns dates in the UTC timezone. However, up until now, not all \DateTime instances returned by this API were using UTC as their timezone. This resulted in the problems described in #119, which were fixed in #120.
Thank you @Clpsplug for finding and reporting the issue as well as verifying the fix!

I really hope timezone handling is working as intended now. But timezone related code always seems prone to issues, so please open an issue if you encounter any problems with this release!

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Correct imperial windspeed unit in forecasts

The imperial wind speed unit for forecasts was incorrectly set to mps instead of mph (#113). Thank you @haydeniv for reporting!

Get current weather by zipcode

You can now retrieve the current weather using a zipcode (see here for official OWM documentation).

// Get current temperature from zip code (Hyderabad, India).
$weather = $owm->getWeather('zip:500001,IN', $units, $lang);
echo 'City: '.$weather->city->name;
echo 'Temperature: '.$weather->temperature;

Wind direction optional

The wind direction is now optional (#101).

UV Index API support

• uv index api support
• no more http for icon urls
• tests

Multiple cities with query endpoint added

• http://openweathermap.org/current#severalid
• #84

Timezone related issues fixed

v2.1.1

Fix multiple timezone related errors, closes #73. (#75)

Better API key support, fixed critical error in temperature calculation

• added automated integration tests (thanks @aseriy!)
• fixed rounding errors in average temperature calculation for forecasts
• use PSR-4 instead of PSR-0 autoloading
• re-arranged OpenWeatherMap constructor arguments while keeping backwards compatibility (you should now pass the api key as first constructor argument)

Fixed wind direction in forecasts

Also doesn't require-dev phpunit anymore.