Finish 2.1.5
Fixed typo in CHANGELOG
Updated README after v2.1

Updated languages and translation data.
Removed OpenWeatherMap reference, added Yahoo! Weather.
Updated Credits
Fixed typo in Spanish string

Also added a note to a string that needs to be fixed.
Preparing for v2.2

- Bumped target SDK version to API 19 (4.4 KitKat)
- Added preliminary changelog info for v2.2
Updated the README for v2.2
Updated IDEA project
Added array values for the new localizations
Updated Italian array values
Added new 2.2 localizations

Added Czech, Dutch, French and Russian strings.
Fixes for French strings
Fixed Dutch translator name
Fixed wrong i18n attribution in some cases
Added still-missing v2.2 languages to arrays.xml
Bumped version to 2.2.0
Finish 2.2.0