The format of email list handled is pretty basic for now:
$ git send-email --to='Foo [off-list ref], bar@example.com'
We thought it would be nice to have a "first-step" version which works
before handling more complex ones such as:
$ git send-email --to='Foo, Bar [off-list ref]'
Is this a regression? I can't send emails to a recipient whose name
contains a comma?