Byte-stuffing and clone patches

Two patches here: one to make a hg clone command in repotool work and one to avoid issues with byte-stuffing. The byte-stuffing problem arises for a line in an event being read in which begins with two dots (so a single byte stuffed dot).

To see the issue in action, run the following on the attached test.fi

reposurgeon 'read <test.fi' '=C edit' '=C edit'

The second edit will report commit messages that are not LF terminated.