Add Progress Bar Support for Page Field

[mosesintech]

After adding a Page field to your form, if you look at the preview you will see a progress bar that fills as you progress through the pages. Above the bar is the page you are on in a text string Step X of Y; I will call this label. Below this is the progress bar with a percentage value reflecting your progress.

If this is added, we should also add a new prop to the GravityForm component called progressBar. I suggest this be an object shaped like this:

interface ProgressBar {
    display?: boolean // should we show the progress bar?
    color?: string // hex color progress bar should be
    label?: string // example: "Step", "Page", "Phase". Result will be `${label} ${currentPage} of ${totalPages}`. If null, hide label.
}