Added botraf (the IRC bot) submodule

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>
Added a simple build system

Each submodule is built and assembled into a zip file named after the submodule
and the git ref that was used as a base.  The build script verifies that no
changes are present within each submodule, to help ensure that builds are
reproducible.

Signed-off-by: Morten Hustveit <morten.hustveit@gmail.com>