Add option to `interpolateProperties` to wrap interpolation in helper

[cibernox]

Example:

{{fa-icon color=boundColor}}

class FaIcon extends BuildTimeComponent {
  constructor() {
    super(...arguments);
    this.styleContent = interpolateProperties('color:$color$', { divisor: '$', skipIfMissingDynamic: true });
  }
}

<i class="fa" style={{if color (concat "color:" color)}}></i>

This option by default is false, because it's a rather convoluted output for what is usually an uncommon use case (so I think, time will tell)