mergetools: add BeyondCompare 4 for Windows
This is a copy of the TortoiseHg configuration, but dropping the 3-way diff and
dirdiff settings (since those aren't supported in core Mercurial), and swapping
the 'parent1', 'parent2', and 'base' literals for `$labellocal`, `$labelother,
and `$labelbase` respectively. (That functionality was apparently never ported
to TortoiseHg.)
Additionally, the single quotes were removed from around these arguments, since
none of the other configs have them.
Differential Revision: https://phab.mercurial-scm.org/D9635
Mercurial
=========
Mercurial is a fast, easy to use, distributed revision control tool
for software developers.
Basic install::
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
Running without installing::
$ make local # build for inplace usage
$ ./hg --version # should show the latest version
See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.