Use standard configurable validation from Atomia.Web.Plugin Validation

* Use AtomiaValidation.js as base for front-end validation.
* Removed validation related code from AtomiaBase.js
* Use standard CheckUsername action from Atomia.Web.Plugin.Validation
* Added trigger of custom event when cart is updated in AtomiaShoppingCart.js
* Moved DomainRegContact from subform into main form. DomainRegContact is now just used for JSON serialization
* Removed unused fields on DomainRegContact
* Removed OrderPageWizzard [sic] structure; only InitializeButtons was actually used.
* Use JavaScript field copy approach for Billing and whois addresses instead of subform and/or specific back-end logic.
* Removed ajax validation of VAT number
* Removed ajax validation of email domain (SimpleDnsPlus.IDNLib)
* Removed *Processed field structure for phone/mobile/fax
* Fixed reloading works on server-side validation failure.

* Updated jQuery Validation Plugin (jquery.validate.js) to version 1.8.1
* Changed default required field message from "Mandatory" to "This field cannot be empty"
* Made VAT number an explicit visible field to fill in instead of a hidden automatically handled field.
* Fixed form labels referencing the correct input field ids.
* Use first name and last name for whois form (same as other addresses) and combine later.
* Made Billing fax field not hidden.
* Standardized whois form field names, ids and order.

Change-Id: I0b9f99238ff4dab2a7b89dd31266aa9b5085f7c2