tests/test-issue436

patchbomb: make `hg email` reusable for other patch sources

Adds two internal options, patches and patchnames, which allow other extensions
to email a given set of patches. The pbranch extension needs this to send its
patches which are diffs between topic branches.

#!/bin/sh

hg init a
cd a
hg -v log -v
hg -v log -v x
true