Make HTML generation configurable

[jmvanel]

For a Scala developper to change or rewrite the HTML generator , possibly with another technology like Mustache or Scala.JS, the code must be made modular, in the spirit of
Chapter 29 Modular Programming Using Objects
http://www.artima.com/pins1ed/modular-programming-using-objects.html#27.3

The situation

The Configuration is modular thanks to filed abstract field config.
So the Configuration could hold a field for the HTML generation implementation.

Currently the HTML generator is a private [html] trait Form2HTML .
It is used by traits TableViewModule and CreationFormAlgo, that instanciate Form2HTMLBanana.

Then TableViewModule and CreationFormAlgo are added by inheritance in the generic application.

There is an attempt at an HTML Form API for front end developer,
trait HTMLFormAPI ,
but it is not used.

[jmvanel]

Here is an example of overriding a function implementing the form:

    override  def makeBackLinkButton(uri: String, title: String = "") = {
    val tit = if (title == "") s" Reverse links for <$uri>" else title
    <button type="button" 
    		class="btn btn-info" readonly="yes" title={ tit } data-value={s"$uri"}
                onclick={ s"backlinks( '$uri' )" } id={ s"BACK-$uri" }>
    		bla    
    </button>

Just paste this in makeDefaultForm2HTML in Form2HTMLBanana.scala, and the Back Link Button will change its aspect.

The same customization can also be made in Application.scala .