dataType needs to be set on $.ajax calls for apps using file:///

dataType needs to be set on $.ajax calls for apps using file:///

Reposting from bug report on  https://github.com/jquery/jquery-mobile/issues/1308

I'm building a PhoneGap app using jQM and found that the $.ajax call inside $.mobile.changePage does not set the dataType to "html." Because of this, webkit loads the page (located at file://some/path//page.html) as a "Document" object rather than just straight up html. jQM expects the response to be an html string rather than a Document object. This causes line 2057 (in jqm 1.0a3) to fail to find the element: 
to = all.find('[data-role="page"], [data-role="dialog"]').first();

I'm guessing that we need to set the dataType to always be "html" since $.mobile.changePage will always be retrieving an html page.