title: Edit NumberCell Using SHIFT + number
body: <p>I think editing NumberCell using &quot;SHIFT&quot; + &quot;number&quot; is not allowed on <code>@silevis/reactgrid</code>.</p>
  <p>On library NumberCellTemplate we have:</p>
  <pre><code>handleKeyDown(cell: Compatible&lt;NumberCell&gt;, keyCode: number, ctrl: boolean, shift: boolean, alt: boolean): { cell: Compatible&lt;NumberCell&gt;; enableEditMode: boolean } {
      if (isNumpadNumericKey(keyCode)) keyCode -= 48;
      const char = String.fromCharCode(keyCode);
      if (!ctrl &amp;&amp; !alt &amp;&amp; !shift &amp;&amp; (inNumericKey(keyCode) || isAllowedOnNumberTypingKey(keyCode))) {
          const value = Number(char);
          if (Number.isNaN(value) &amp;&amp; isAllowedOnNumberTypingKey(keyCode))
              return { cell: { ...this.getCompatibleCell({ ...cell, value }), text: char }, enableEditMode: true }
          return { cell: this.getCompatibleCell({ ...cell, value }), enableEditMode: true }
      }
      return { cell, enableEditMode: keyCode === keyCodes.POINTER || keyCode === keyCodes.ENTER }
  }
  </code></pre>
  <p>Is there any way to let users use &quot;SHIFT&quot; + number?</p>
  <p>Thanks</p>