refactor settings into a class; add render method

src/app/tabs/run-tab.js

@@ -11,7 +11,7 @@ var Card = require('../ui/card')
 var Recorder = require('../../recorder')
 var css = require('./styles/run-tab-styles')
 
-var settingsUI = require('./runTab/settings.js')
+var SettingsUI = require('./runTab/settings.js')
 var contractDropdownUI = require('./runTab/contractDropdown.js')
 
 function runTab (opts, localRegistry) {
@@ -128,9 +128,10 @@ function runTab (opts, localRegistry) {
   /* -------------------------
        MAIN HTML ELEMENT
   --------------------------- */
+  var settingsUI = new SettingsUI(container, self)
   var el = yo`
   <div>
-    ${settingsUI(container, self)}
+    ${settingsUI.render()}
     ${contractDropdownUI(self.event, self)}
     ${recorderCard.render()}
     ${self._view.instanceContainer}