Add ".. -*- coding: utf-8-with-signature -*-" to the first line of each .rst
file. This tells emacs to treat the file contents as utf-8, and also to prepend
a so-called utf-8 "bom" marker at the beginning of the file. This patch also
prepends those markers to each of those files.
Check for the existence of any of them and if any are found raise exception which will abort the startup of the node.
This is a backwards-incompatible change for anyone who is still using old-style configuration files.
fixes#1385
