Add colored icon to BottomTabs screen

playground/src/app.js

         orientation: ['portrait']
       },
       bottomTab: {
-        iconColor: '#1B4C77',
-        selectedIconColor: '#0f0',
         textColor: '#1B4C77',
         selectedTextColor: '#0f0',
         fontFamily: 'HelveticaNeue-Italic',

playground/src/screens/WelcomeScreen.js

                         },
                         bottomTab: {
                           text: 'Tab 1',
-                          icon: require('../images/one.png'),
-                          selectedIcon: require('../images/one.png'),
+                          icon: require('../images/colored_tab_icon.png'),
                           testID: testIDs.FIRST_TAB_BAR_BUTTON
                         }
                       }
                   bottomTab: {
                     text: 'Tab 2',
                     icon: require('../images/two.png'),
+                    iconColor: '#1B4C77',
+                    selectedIconColor: '#0f0',
                     testID: testIDs.SECOND_TAB_BAR_BUTTON
                   }
                 }
                   bottomTab: {
                     text: 'Tab 3',
                     icon: require('../images/one.png'),
+                    iconColor: '#1B4C77',
+                    selectedIconColor: '#0f0',
                     selectedIcon: require('../images/one.png')
                   }
                 }