Move cryptographic hashing procedures to crypto folder. (#2306)

Step towards https://github.com/paritytech/polkadot-sdk/issues/1975

As reported
https://github.com/paritytech/polkadot-sdk/issues/1975#issuecomment-1774534225
I'd like to encapsulate crypto related stuff in a dedicated folder.

Currently all cryptographic primitive wrappers are all sparsed in
`substrate/core` which contains "misc core" stuff.

To simplify the process, as the first step with this PR I propose to
move the cryptographic hashing there.

The `substrate/crypto` folder was already created to contains `ec-utils`
crate.

Notes:
- rename `sp-core-hashing` to `sp-crypto-hashing`
- rename `sp-core-hashing-proc-macro` to `sp-crypto-hashing-proc-macro`
- As the crates name is changed I took the freedom to restart fresh from
version 0.1.0 for both crates

---------

Co-authored-by: Robert Hambrock <roberthambrock@gmail.com>

substrate/primitives/statement-store/Cargo.toml

@@ -19,6 +19,7 @@ targets = ["x86_64-unknown-linux-gnu"]
 codec = { package = "parity-scale-codec", version = "3.6.1", default-features = false, features = ["derive"] }
 scale-info = { version = "2.10.0", default-features = false, features = ["derive"] }
 sp-core = { path = "../core", default-features = false }
+sp-crypto-hashing = { path = "../crypto/hashing", default-features = false }
 sp-runtime = { path = "../runtime", default-features = false }
 sp-std = { path = "../std", default-features = false }
 sp-api = { path = "../api", default-features = false }
@@ -52,6 +53,7 @@ std = [
 	"sp-api/std",
 	"sp-application-crypto/std",
 	"sp-core/std",
+	"sp-crypto-hashing/std",
 	"sp-externalities/std",
 	"sp-runtime-interface/std",
 	"sp-runtime/std",

substrate/primitives/statement-store/src/lib.rs

@@ -87,7 +87,7 @@ mod ecdsa {
 /// Returns blake2-256 hash for the encoded statement.
 #[cfg(feature = "std")]
 pub fn hash_encoded(data: &[u8]) -> [u8; 32] {
-	sp_core::hashing::blake2_256(data)
+	sp_crypto_hashing::blake2_256(data)
 }
 
 /// Statement proof.
@@ -632,7 +632,7 @@ mod test {
 		statement.sign_ecdsa_private(&secp256k1_kp);
 		assert_eq!(
 			statement.verify_signature(),
-			SignatureVerificationResult::Valid(sp_core::hashing::blake2_256(
+			SignatureVerificationResult::Valid(sp_crypto_hashing::blake2_256(
 				&secp256k1_kp.public().0
 			))
 		);