def credentials=(string)
      user, pass = string.split(":")
      dcp = HtmlUnit::DefaultCredentialsProvider.new
      dcp.addCredentials(user, pass)
      @webclient.setCredentialsProvider(dcp)
    end
def credentials=(string)
      user, pass = string.split(":")
      dcp = HtmlUnit::DefaultCredentialsProvider.new
      dcp.addCredentials(user, pass)
      @webclient.setCredentialsProvider(dcp)
    end
Set the credentials used for basic HTTP authentication. (Celerity only)

 Example:
   browser.credentials = "username:password"

 @param [String] A string with username / password, separated by a colon