Fix response body newline bug

[gugl]

just found out that the ring-servlet is appending a newline to the request body when it updates the HttpServletResponse with a string. this newline triggered a bug on some of our really strict client libraries and is (as far as i can see) appended without a reason. in order to fix this i just replaced the call to println with a call to print. although this is a really simple commit, we would love to see it in upstream and in the next release to be able to switch back to the official ring version.

best regards
gugl

[weavejester]

Turns out I was the original author of that line of code (according to git blame). I agree that it should be print, rather than println. I'll merge the changes.