Add feature for skipping rows using JXLS Reader

[Jeff Jensen]

Sometimes a sheet has rows we don't want to load and manually removing those rows presents additional issues, so this feature idea is for having a way to declare in the XML file one or more sheet rows to ignore.

I'm thinking of a simple idea such as:

<skipRows>
  <rowNum>8</rowNum>
  <rowNum>12</rowNum>
</skipRows>

or somehow specifying criteria:

<skipRows>
  <rowCriteria col="B" operation="equals">4</rowCriteria>
</skipRows>

Using multiple <loop> sections could accomplish this, but that doesn't scale well with need to skip more than a couple of rows (same data in multiple loops).