mixnode: replaced base64 with base58

Cargo.lock

@@ -1382,7 +1382,7 @@ name = "nym-mixnode"
 version = "0.3.3"
 dependencies = [
  "addressing",
- "base64 0.11.0",
+ "bs58",
  "built",
  "clap",
  "curve25519-dalek",

mixnode/Cargo.toml

@@ -8,7 +8,7 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-base64 = "0.11.0"
+bs58 = "0.3.0"
 clap = "2.33.0"
 curve25519-dalek = "1.2.3"
 dotenv = "0.15.0"

mixnode/src/node/mod.rs

@@ -31,7 +31,7 @@ pub struct Config {
 impl Config {
     pub fn public_key_string(&self) -> String {
         let key_bytes = self.public_key.to_bytes().to_vec();
-        base64::encode_config(&key_bytes, base64::URL_SAFE)
+        bs58::encode(&key_bytes).into_string()
     }
 }
 
@@ -232,8 +232,7 @@ impl MixNode {
         let directory_cfg = directory_client::Config {
             base_url: self.directory_server.clone(),
         };
-        let pub_key_str =
-            base64::encode_config(&self.public_key.to_bytes().to_vec(), base64::URL_SAFE);
+        let pub_key_str = bs58::encode(&self.public_key.to_bytes().to_vec()).into_string();
 
         rt.spawn({
             let presence_notifier = presence::Notifier::new(&config);