Forecast bug fix

Original Issue: #362

I had noticed that I received different results for q?=forecast+63501 and q?=weather+63501
I traced the error to the $weather_qr regex in lib/DDG/Spice/Forecast.pm, wrote some new tests and found a solution I believe to be valid.

As @moollaza pointed out, DDG has a special API for Forecast.io and I have not been able to test this live.