Add support for centos (and others in the RH family)

Provided that the epel yum repo is configured (adding yum-epel to the runlist is enough), this cookbook can now install x11vnc and configure it as a service on CentOS.
not exactly, your original diff was removing the end of line characters which was not great... but I meant only the files you touched, and technically I didn't mean a "new line" or "extra line" at the end of the file but a "line break" at the end of the last line, if that makes sense... (vi editor will do the right thing...)