Reading the RST spec, I was trying to get breaks to appear by entering the double spaces after the lines in the code blocks. It does not work anyway, and, as pointed out, I've removed.

Additionally it does not appear there is turnserver.conf.default, but rather, just /etc/turnserver.conf.

initial WIP of a tentative preview_url endpoint - incomplete, untested, experimental, etc. just putting it here for safekeeping for now