Extend Angular Form Builder

app.js

var fbScope = angular.element('#form-builder').scope();
fbScope.formComponentGroups.existing = {
  title: 'Existing Fields',
  panelClass: 'subgroup-accordion-container',
  subgroups: {} 
};
fbScope.formComponentsByGroup.existing = {
  'firstName': {
    type: 'textfield',
    key: 'firstName',
    label: 'First Name'
    ...
    ...
  },
  'lastName': {
    type: 'textfield',
    key: 'lastName',
    label: 'Last Name'
    ...
    ...
  }
};