Fix time-formatting

[jotoeri]

This reincludes the moment-locales into the forms-bundle, so @nexctloud/moment can use it.

• Allows moment to format the date on Results - Fix Inconsistent timestamp when exporting as csv #606
• Allows moment on the new Date-QuestionType to format the date Add Date & Datetime Component #672
• Allows moment on sidebar to format automatically, no manual loading necessary anymore.
• Indeed, this increases forms-main bundle size from 1.95MiB to 2.15MiB, but compared to other apps (Mail 4.3MiB, Deck 2.72MiB, Contacts 2.6MiB), that still seems ok to me. However one could probably find other ways to further reduce the single-package-size.