Bug#744815: please compile against openssl

[Jamie McClelland]

I see that this is an old bug and would really like to see it resolved. 

I have had mixed success getting apache2 or ngninx to proxy icecast2. It
makes trouble shooting a lot harder.

And, without be able to access icecast2 over https, we get mixed content
warnings when displaying a stream on an https page.

>From my tests, it compiles fine on amd64/jessie - I just needed to
install the libssl-dev package before building.