weather: forecast up to 10 days

This service needs api key. For now I put it straightly into the url
It will need to be replaced, like in perl with {{ENV_APIKEY}} , but not sure if python supports this. Gonna look at it deeply.

Signed-off-by: Adrian Matejov <a.matejov@centrum.sk>
'Cause if there is just query `!weather Liptovský Mikuláš` args[1] there is not really date. So it throws exception and therefore current date is get. If you have any better solution please let me know.