* manifest.scm: Fix alternate command line invocation (which would not
consider 'manifest.scm'). Use specifications instead of packages. Remove
perl (now in the guix package's native inputs). Add b4, git, git:send-email,
mumi, nss-certs, openssl and patman to the manifest.
Change-Id: I49d92dda059856ce217cea9054a466a1754dcf94
Signed-off-by: Maxim Cournoyer <maxim.cournoyer@gmail.com>
