Adding support for "NO-HASH" when signing with ECDSA

[nirfireblocks]

Hi @microshine,

We ran into a use case where the data to be signed via ECDSA is already hashed, and should not be hashed again. As it wasn't available, I added the option to sign via ECDSA with the hash algorithm "NO-HASH". I created two pull requests:
node-webcrypto-p11: #82
webcrypto-core: PeculiarVentures/webcrypto-core#64

These are tiny PRs, I tested them and they worked great.

Could you please merge them into the master branch?

Thanks,
Nir