Revert "timezone: Remove geoclue integration... for now..."

This reverts commit b7dca1d7ed9b03154462b8a56cb6517b2d705185.
timezone: Finish up geoclue integration
timezone: Tweak the page layout to better match mockups
timezone: Improve the timezone description shown in the ui
timezone: Stop geolocation if it hasn't finished in time
timezone: Remove markup from translatable string
Further improve an enterprise login string

https://bugzilla.gnome.org/show_bug.cgi?id=726487