Verify response type and fix exception reporting

Ran into this problem when trying to do a bulk request for around 750 names. The Apache server responded with a 414 request below, and the exceptions from the `json` module confused me so I thought I would help out the next person that runs into this issue. After all, you gets 2500 requests a day, so this quantity isn't _that_ ridiculous if you don't consider how the sausage is made.

```html
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>414 Request-URI Too Large</title>
</head><body>
<h1>Request-URI Too Large</h1>
<p>The requested URL's length exceeds the capacity
limit for this server.<br />
</p>
<hr>
<address>Apache/2.2.15 (CentOS) Server at vps-1154848-20754.manage.myhosting.com Port 80</address>
</body></html>
```