Add Timezone field in IdentityUI register page

[panoukos41]

• Add flag RegisterRequireZoneInfo in IdentityUIOptions to enable UI and validation.
• Add ZoneInfo type.
• Update validation logic of RegisterInputModelValidator
• Update translations of Register.el.resx and RegisterInputeModelValidator.el.resx
• Update pages with input + datalist elements
• Add JS to preselect user's timezone from the browser