export: serialize revisions to be exported per destination file
Prepares for porting to the formatter API, where we can't simply append
to existing files because JSON can't be streamed for example.
The modemap hack is removed since cmdutil.export() was the only user.
I also made the destination filename printed only once.
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.