title: Implementing NGX Datatable filtering on all columns
body: <p>I've been trying to get this working with no luck. I've been referencing these resources for help:
  <a href="http://swimlane.github.io/ngx-datatable/#filter" rel="noreferrer">http://swimlane.github.io/ngx-datatable/#filter</a><br>
  <a href="https://github.com/swimlane/ngx-datatable/blob/master/demo/basic/filter.component.ts" rel="noreferrer">https://github.com/swimlane/ngx-datatable/blob/master/demo/basic/filter.component.ts</a></p>
  
  <p>Basically i just want to allow my filter to apply to more than a single column, without implementing code to handle every column. (Some datatables have 20+ columns!)</p>
  
  <p>Example Code:  </p>
  
  <pre><code>//HTML
    &lt;input type='text' placeholder='Filter' (keyup)='updateFilter($event.target.value)' /&gt;
  
    &lt;ngx-datatable
      class="material"
      columnMode="force"
      [columns]="gridProperties.FilteredColumns"
      [footerHeight]="50"
      [loadingIndicator]="gridLoadingIndicator"
      [rows]="filteredList"
      [scrollbarH]="false"
      [scrollbarV]="true"
      [selected]="selectedItem"
      [selectionType]="'single'"
      style="min-height:400px;"&gt;
    &lt;/ngx-datatable&gt;
  
  //TYPESCRIPT
    public items: Item[];
  
    updateFilter(filterValue) {
      const lowerValue = filterValue.toLowerCase();
  
      this.filteredList = this.items.filter(item =&gt; item.name.toLowerCase().indexOf(lowerValue) !== -1 || !lowerValue);
    }
  </code></pre>
  
  <p>Here I am obviously just handling filtering for the 'name' property of my items array. This works great as is, but like I had mentioned, if the grid contains many columns I'd like one method to handle all of them. Any help or tips are appreciated.</p>