removed 503 redirects, errors now stay on the same url; reconfigured logging to send page error email to admins; added logger for missing pycountry.db library; cleaned up 404 and 500 html templates, closes #393
Merge pull request #397 from gwu-libraries/t393-log-errors-before-redirect

removed 503 redirects, errors now stay on the same url; reconfigured log...