Compact 65-byte signature

[hoanglu14]

What problem does this feture solve?

I couldn't find any function to support compact signature (65 bytes: header + r + s) using this framework. This can be done if you guys also include secp256k1_recovery.h in BitcoinKitPrivate. Then, I can just simply make my own compact signature with secp256k1_ecdsa_recoverable_signature_serialize_compact

I also cloned this project and tried to do what I said above. However I ran into a compile error saying

I have no idea why so a little help would be very appreciated.

[usatie]

@hoanglu14 Sorry for my late reply. Your suggestion is good. That feature should be implemented in the future.

Also, can you give me more information about the compile error?