[WU] Add personal api and fix to full working condition.

This cherry picks https://github.com/XBMC-Addons/weather.wunderground/commit/a2c10e704ffb5ab21e8146dc38541bbedd81506f

With the above cherry pick only conflict resolution was required when rebasing on master.

The remainder of commits are required for addon to fully work again using this new method.
Finally bumped the addon version again and updated all changelogs in process to reflect all changes.

Tested against current Kodi master fully working