rust-core: updated copyright notice
The intention here is to put an email address that actually
works (I did have full personal copyrights with my
former affiliation).
It is also an opportunity to acknowledge that I've not been
the only one to work on this file.
Differential Revision: https://phab.mercurial-scm.org/D7781
Mercurial's documentation is kept in reStructuredText format, which is
a simple plain text format that's easy to read and edit:
http://docutils.sourceforge.net/rst.html
It's also convertible to a variety of other formats including standard
UNIX man page format and HTML. You'll need to install Docutils:
http://docutils.sourceforge.net/
Use the Makefile in this directory to generate the man and HTML pages.