CMS-3707 Versioning and workspaces - Add support for workspaces in portal

Added workspace and context
CMS-3715 Add context to SiteService

Made SiteService use provided context
CMS-3719 - Add context to AttachmentService

Yes
CMS-3707 Versioning and workspaces - Add support for workspaces in portal

Added workspace to portal domain. Fixed workspace-init, updated test.
CMS-3720 Append workspace to all paths

A bit messy with the 4 arguments method in UriHelper, but Ill let it be for now since its going to be heavy changes in the url-rendering stuff
CMS-3707 Versioning and workspaces - Add support for workspaces in portal

fixed merge conflicts after major portal changes