Adds a @Input() showDeclaredFieldsOnly option which tells the grid to
avoid showing auto-generated columns by default and only show those
declared in the markup.
Also repairs a grid column sorting/insert bug where declared columns
would be displayed in the wrong order when mixed with auto columns.
Signed-off-by: Bill Erickson <berickxx@gmail.com> Signed-off-by: Dan Wells <dbw2@calvin.edu>