Format of XBearerSignature

Created by: alexvanin

Signature is a concatenation of data and salt fields of signature result from wallet-connect.

{
    "publicKey": "03bd9108c0b49f657e9eee50d1399022bd1e436118e5b7529a1b7cd606652f578f",
    "data": "1d663651aa4387a32af4d09d437f4e6b405085192df6f313b851a543d0ca63c5d256c148d6f5914ba177ce5d0a3d25615bc8d35e95d54081a7611c7e422f1c84",
    "salt": "5b5cdb4349f7a2adc40624f75ccf1a5b",
    "messageHex": "010001f07935623563646234333439663761326164633430363234663735636366316135620a1004d7fd2f5f4310fd7bfdfd5efd66fd121b0a1935717d0e7a6b4bfd7859fd3bfdfd29014b51670d6bfd281a04086c180822210272fdfd6426765720fd68fd10fd2753fd4458fd17576f3afd564c315807563204080110010000"
}

REST Gateway expects base64 encoded value. However it is much easier to concatenate two hex encoded strings from result structure on the front end. Also public key is already passed in header as hex.

/cc @mike-petrov @KirillovDenis