update wunderground addon

due to recent changes in xbmc, the wunderground addon is currently broken.
this pr fixes that issue as well as several other minor bugs.

- fix animated radar images
- added support for 5 locations
- fix possible incorrect display of location name
- removed old backward compatibility code
- added localtime and localdate infolabels
- added yyyy-mm-dd format for regions that use this format
- fix remove return chars in rss infolabel
- fix corrupted alert message
- fix potential crash on invalid json response
- fix api error response check
- added gzip compression support
- language files update