[PATCH 1/2] gnu: Add ruby-mail. A gem needed at runtime for notmuch-vim.
[PATCH 2/2] gnu: Add notmuch-vim. I'm not sure about the propagation: Without vim-full (ruby enabled), notmuch and ruby-mail this vim plugin will not work. Propagation seems like the way to go here, but I'm open to suggestions. All this build system does is copy some files around.
