Change the names of variables $plotarea and $dataseriesLabel to $plotArea and $dataSeriesLabel, respectively, to make it camel case compliant
Merge pull request #377 from dmelo/develop

Change the names of two variables on the examples, to make it camel case
Invalid Index

This happened when I tried to load an Excel doc that was exported by Google Docs. I'm guessing there is no author information or something? I dunno but this fixed worked.
Merge pull request #381 from shrimpwagon/patch-1

Invalid Index