Make web quickstart work better in PhoneGap and Mac

* Add `<meta name='viewport'>`, since PhoneGap for WP7.5/8 strictly
requires it
* Explicitly fetch external scripts via https://, since
protocol-relative URLs won't work inside PhoneGap (note: this doesn't
risk extra warnings, because we were already fetching the
MobileServices.Web-xxx.js over https)
* Show any errors on screen (not just in console, since it's hard to see the console in PhoneGap)
* Fix the UTF-8 encoding issues we saw on Chrome for Mac. (Sample bug report: http://social.msdn.microsoft.com/Forums/en-US/azuremobile/thread/97b23507-b30e-4001-a967-d7127c0fc314)