Support for current time, preparation for weather.
Tiny fixes, TODOs
Just PEP8
Allowing asking for weather
Interpreting departure, arrival and weather time

Now it's possible to search for connection with a given arrival time.
First basic attempt at using the OpenWeatherMap API
Merge branch 'master' into time_weather
Basic weather working.

TODO: Add declension to degrees.
Simple weather dialogue finished

Remaining problems: undefined behavior when changing time from relative to absolute
More concise printing the dialogeu state.
Adding various time expressions to SLU bootstrap
Adding default times for ampm slot values
Merge branch 'master' into time_weather
Implemented correct handling of the deny DAI.
Added to policy generation of confirm and select dialogue acts.
Merged OD's changes.