bundle: prevent implicite bundling of internal changeset
Now that the two mains source of on-disk bundle are preventing the inclusion of
internal changesets in their bundling. We can add a lower level check that
would prevent any other leakage of internal-phase changesets.
We keep the door open to some usage, like the temporary bundle using during
strip for example.
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.