Add support for bazel to our pbuilder world

- Add gnupg to the pbuilder base.tgz, to allow us to install keys with
- Import bazel's key into our repository, and install it into pbuilder
via the D05deps hook
- Add bazel to sources.list with the D05deps hook, as well

Change-Id: I670df8e752937b896c834ee514052ff719878709
3 files changed