* Upgrade JNI interface
* Input signatures can be DER or compact format, output signatures are always in compact format
* Input public keys can be compressed or uncompressed, output public keys are always uncompressed
* Name and parameters match libsecp256k1's
* JNI implementation is now straightforward
No more ByteBuffers
Exceptions are thrown in case of failures
* Update src/nativeMain/kotlin/fr/acinq/secp256k1/Secp256k1Native.kt
* Add public key compression method
Co-authored-by: Salomon BRYS <salomon.brys@gmail.com>