imerge: fix ancestor calculation If wctx already has two parents, ancestor calculation is wrong. Normally merge is called before wctx gets the second parent, so we simulate this in imerge by temporarily popping the second parent before calling filemerge. Highly dirty. This patch also handles the ParseError move from cmdutil to dispatch.

Basic install:

 $ make            # see install targets
 $ make install    # do a system-wide install
 $ hg debuginstall # sanity-check setup
 $ hg              # see help

See http://www.selenic.com/mercurial/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.