Added a method to retrieve the actual bytes of BLOB

... which is probably more useful than the getContent() method

src/main/java/org/kohsuke/github/GHBlob.java

@@ -1,30 +1,63 @@
 package org.kohsuke.github;
 
+import org.apache.commons.codec.binary.Base64InputStream;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.io.UnsupportedEncodingException;
+import java.net.URL;
+
 /**
  * @author Kanstantsin Shautsou
+ * @author Kohsuke Kawaguchi
+ * @see GHRepository#getBlob(String)
  * @see <a href="https://developer.github.com/v3/git/blobs/#get-a-blob">Get a blob</a>
  */
 public class GHBlob {
     private String content, encoding, url, sha;
     private long size;
 
-    public String getEncoding() {
-        return encoding;
-    }
-
-    public String getUrl() {
-        return url;
+    /**
+     * API URL of this blob.
+     */
+    public URL getUrl() {
+        return GitHub.parseURL(url);
     }
 
     public String getSha() {
         return sha;
     }
 
+    /**
+     * Number of bytes in this blob.
+     */
     public long getSize() {
         return size;
     }
 
+    public String getEncoding() {
+        return encoding;
+    }
+
+    /**
+     * Encoded content. You probably want {@link #read()}
+     */
     public String getContent() {
         return content;
     }
+
+    /**
+     * Retrieves the actual bytes of the blob.
+     */
+    public InputStream read() {
+        if (encoding.equals("base64")) {
+            try {
+                return new Base64InputStream(new ByteArrayInputStream(content.getBytes("US-ASCII")), false);
+            } catch (UnsupportedEncodingException e) {
+                throw new AssertionError(e);    // US-ASCII is mandatory
+            }
+        }
+
+        throw new UnsupportedOperationException("Unrecognized encoding: "+encoding);
+    }
 }