Grids with width in % in IE are broken

[HristoP96]

Description

Grids with width in % do not render properly in IE because of these code snippets:

   const computed = this.document.defaultView.getComputedStyle(this.nativeElement);

   if (this._width && this._width.indexOf('%') !== -1) {
      /* width in %*/    
        const width = parseInt(computed.getPropertyValue('width'), 10);

The problem is that in IE computed.getPropertyValue('width') returns 100% if the grid width is set 100% and when you calculate const width = parseInt(computed.getPropertyValue('width'), 10); it return 100 which sets the grids width to 100px.

Steps to reproduce

Open this link in IE:
https://www.infragistics.com/products/ignite-ui-angular/angular/components/grid.html

Result

This grid is broken:

Expected result

The grid to render properly;

[HristoP96]

The rendering issues were caused due to not enabling the Autoprefixer plugin to work with grid layouts.

A decision was made that this enabling will be done only on customer side (if they want to use our controls in IE 11).

This pull request provides a documentation on how and why the customers should enable the autoprefixer for grid layout.