Changes to setup to handle harvest apps with welcome pages

This PR tried addressing the issue
https://github.com/cbmi/cilantro/pull/659

But the solution was app specific. The problem was determined to be omop harvest returning at status code 302 and the ajaxError code does not handle this case.

Signed-off-by: Sheik Hassan <solergiga@yahoo.com>
Rather than checking the status text, check the response code range `xhr.status >= 300 && xhr.status < 400`