Merge pull request #181 from andresousa/issue-172

Expose errorDescription.

Author: TonioMacaronio

Sources/web3swift/Web3/Web3.swift

@@ -18,7 +18,7 @@ public enum Web3Error: Error {
     case generalError(err:Error)
     case unknownError
 
-    var errorDescription: String {
+    public var errorDescription: String {
         switch self {
 
         case .transactionSerializationError: