Added config setting for default document type property; used setting to set default new property type
Moved setting for DefaultDocumentTypeProperty from GlobalSettings to UmbracoSettings
Merge branch 'wip-u4-1949' of https://github.com/AndyButland/Umbraco-CMS into AndyButland-wip-u4-1949
defaultDocumentTypeProperty is no longer case-sensitive. Added to the Release config as well so it makes it into the umbraco downloadable package.