ECDSA Support in signer (#1064)

* Add ecdsa support to signer

* Remove nix. Cleanup.

* remove ecdsa example and small tidy

* fmt

* fix wasm test

* feature flag ecdsa/sr25519 support, use global signing context

* clippy fix

* ensure signers all impl Signer trait in doc test

* fix CI

* fix digner test

* remove dead code warnings when no features enabled

* move dead code attr to right place

* fix random clippy error that popped up

---------

Co-authored-by: Lech Głowiak <lech.glowiak@gmail.com>

Cargo.lock

@@ -3314,7 +3314,16 @@ version = "0.24.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6b1629c9c557ef9b293568b338dddfc8208c98a18c59d722a9d53f859d9c9b62"
 dependencies = [
- "secp256k1-sys",
+ "secp256k1-sys 0.6.1",
+]
+
+[[package]]
+name = "secp256k1"
+version = "0.27.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25996b82292a7a57ed3508f052cfff8640d38d32018784acd714758b43da9c8f"
+dependencies = [
+ "secp256k1-sys 0.8.1",
 ]
 
 [[package]]
@@ -3326,6 +3335,15 @@ dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "secp256k1-sys"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "70a129b9e9efbfb223753b9163c4ab3b13cff7fd9c7f010fbac25ab4099fa07e"
+dependencies = [
+ "cc",
+]
+
 [[package]]
 name = "secrecy"
 version = "0.8.0"
@@ -3727,7 +3745,7 @@ dependencies = [
  "regex",
  "scale-info",
  "schnorrkel 0.9.1",
- "secp256k1",
+ "secp256k1 0.24.3",
  "secrecy",
  "serde",
  "sp-core-hashing",
@@ -3807,7 +3825,7 @@ dependencies = [
  "log",
  "parity-scale-codec",
  "rustversion",
- "secp256k1",
+ "secp256k1 0.24.3",
  "sp-core",
  "sp-externalities",
  "sp-keystore",
@@ -4290,6 +4308,7 @@ dependencies = [
  "pbkdf2 0.12.2",
  "regex",
  "schnorrkel 0.10.2",
+ "secp256k1 0.27.0",
  "secrecy",
  "sha2 0.10.7",
  "sp-core",