Use /dev/urandom, to not block on startup.
Use /dev/urandom, to not block on startup.

Issue:	        #4
Reported by:	oteren

dsanders11/rtpproxy,synety-jdebp/rtpproxy,synety-jdebp/rtpproxy,jevonearth/rtpproxy,Vocalocity/rtpproxy-pre,jevonearth/rtpproxy,sippy/rtpproxy,hongbinz/rtpproxy,Vocalocity/rtpproxy-pre,dsanders11/rtpproxy,synety-jdebp/rtpproxy,synety-jdebp/rtpproxy,Vocalocity/rtpproxy-pre,hongbinz/rtpproxy,jevonearth/rtpproxy,hongbinz/rtpproxy,Vocalocity/rtpproxy-pre,dsanders11/rtpproxy,sippy/rtpproxy,sippy/rtpproxy,hongbinz/rtpproxy,jevonearth/rtpproxy