Derive Serialize trait for Signature

[Fiono11]

How can I derive the Serialize trait for Signature? I don't find any Signature struct, only InternalSignature. Are they the same? This is confusing.

[isislovecruft]

The naming of InternalSignature is due to my writing the crate as originally having a Signature struct, however this had a naming conflict once we started using @tarcieri's signature traits crate. We could potentially derive Serialize for InternalSignature, but to my knowledge there were issues with some serialisation formats not round-tripping, and hence the preferred way to serialise was to call to_bytes().