title: Extend Payment method on onepagecheckout view and controller
body: <p>I have developed own payment plugin in nopCommerce 3.90 version.</p>
  
  <p>I want to call <code>OpcLoadStepAfterShippingMethod</code> method from my own plugin's controller and also want to extend <code>OpcPaymentMethods</code> viewpage.</p>
  
  <p>I have already extend default <code>onepagecheckout</code> view page and controller for that from my plugin.</p>
  
  <p>Please give me solution!</p>