Feat/clouds/restructure

Major change to code design
- New discrete meter class to display various weather information
- Each weather component (clouds, precipitation, wind, etc) will be shown using a meter
- For each weather component, I will either subclass the general meter class or create a different data source
- For clouds, I made a specific data source for the meter
  - Contains logic to determine which cloud image to display in the meter

@rburr @blakecarrier @lukesteffen