Updating all ngGrid controls with percentages instead of fixed widths, a...

Updating all ngGrid controls with:
- percentages instead of fixed widths
- auto height and min-height set
- default sort column
- moved all ngGrid styles to app.less
- removed Preview button from layers table as it's redundant
- added row selection instead of cell selection
- modified cursors for editing cell text and link click
- removed sorting from columns that don't need to sort