Add mwixnet code to master (#726)

* add all comsig code, update to master branch

* refactor code into libwallet, remove some redundancy and update type exports

* added api calls and unit test for comsig request creation

* Addition of JSON-RPC mwixnet function call

* attempt to debug invalid params

* additions to support json doctesting for comsig creation

* tweaks to testing and documentation updates

* dependencies for tests

Cargo.lock

@@ -926,12 +926,6 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
-[[package]]
-name = "fake-simd"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e88a8acf291dafb59c2d96e8f59828f3838bb1a70398823ade51a84de6a6deed"
-
 [[package]]
 name = "fastrand"
 version = "2.1.1"
@@ -1569,6 +1563,7 @@ dependencies = [
  "blake2-rfc",
  "bs58",
  "byteorder",
+ "chacha20",
  "chrono",
  "curve25519-dalek 2.1.3",
  "ed25519-dalek",
@@ -1578,6 +1573,7 @@ dependencies = [
  "grin_util",
  "grin_wallet_config",
  "grin_wallet_util",
+ "hmac 0.12.1",
  "lazy_static",
  "log",
  "num-bigint",
@@ -1587,7 +1583,7 @@ dependencies = [
  "serde",
  "serde_derive",
  "serde_json",
- "sha2 0.8.2",
+ "sha2 0.10.8",
  "strum",
  "strum_macros",
  "thiserror",
@@ -3617,18 +3613,6 @@ dependencies = [
  "unsafe-libyaml",
 ]
 
-[[package]]
-name = "sha2"
-version = "0.8.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a256f46ea78a0c0d9ff00077504903ac881a1dafdc20da66545699e7776b3e69"
-dependencies = [
- "block-buffer 0.7.3",
- "digest 0.8.1",
- "fake-simd",
- "opaque-debug 0.2.3",
-]
-
 [[package]]
 name = "sha2"
 version = "0.9.9"