Prepare release 0.2.8

Author: Ephenodrom

sdk-client/src/main/java/org/domainrobot/sdk/client/Domainrobot.java

@@ -76,7 +76,7 @@ public class Domainrobot {
 	 */
 	public TrustedApplicationClient trustedApplication;
 
-	private String version = "0.2.6";
+	private String version = "0.2.8";
 
 	/**
 	 * <p>