* debian/upstream-signing-key.asc: Add keys from upstream.
* Rename: debian/upstream-signing-key.asc -> debian/upstream/signing-key.asc
* debian/watch: Make use of the signing key from upstream.
* debian/upstream-signing-key.asc: Add keys from upstream.
* Rename: debian/upstream-signing-key.asc -> debian/upstream/signing-key.asc
* debian/watch: Make use of the signing key from upstream.