Added EcKey constructor signatures to make clientName and envUrl opti…

…onal. Updated README to reflect this change

README.md

@@ -16,12 +16,12 @@ json-simple
 Getting Started
 ---------------
 
-Log into your BitPay merchant account and generate a Private Key and SIN. Then all you need to do is instantiate a BitPay object, and pass in your private key and the SIN.
+Log into your BitPay merchant account and generate a Private Key. Then all you need to do is instantiate a BitPay object, and pass in your private key.
 
 ```java
 String privateKey = KeyUtils.readBitcoreKeyFromFile(privateKeyFile);
 ECKey key = KeyUtils.loadKey(privateKey);
-this.bitpay = new BitPay(key, SIN);
+this.bitpay = new BitPay(key);
 ```
 
 ####Create an invoice

src/controller/BitPay.java

@@ -109,11 +109,37 @@ public BitPay(ECKey ecKey, String clientName, String envUrl) throws BitPayExcept
     {
         _ecKey = ecKey;
         this.deriveIdentity();
+
+        if (clientName.equals(BITPAY_PLUGIN_INFO))
+        {
+            try {
+                clientName += " on " + java.net.InetAddress.getLocalHost();
+            } catch (UnknownHostException e) {
+                clientName += " on unknown host";
+            }
+        }
+        // Eliminate special characters from the client name (used as a token label).  Trim to 60 chars.
+        _clientName = clientName.replaceAll("[^a-zA-Z0-9_ ]", "_");
+        if (_clientName.length() > 60)
+        {
+            _clientName = _clientName.substring(0, 60);
+        }
+
         _baseUrl = envUrl;
 	    _httpClient = HttpClientBuilder.create().build();
         this.tryGetAccessTokens();
     }
 
+    public BitPay(ECKey ecKey, String clientName) throws BitPayException
+    {
+        this(ecKey, clientName, BITPAY_URL);
+    }
+
+    public BitPay(ECKey ecKey) throws BitPayException
+    {
+        this(ecKey, BITPAY_PLUGIN_INFO, BITPAY_URL);
+    }
+
     public String getIdentity()
     {
         return _identity;