Handle null or empty columns array.
Merge branch 'master' of https://github.com/jdereg/n-cube
Updated Object[] to use Groovy Expressions instead of writing out in the Array format.  Added Tests for Null column items.  Updated to handle byte[] binary type better, too.
Merge branch 'master' of https://github.com/jdereg/n-cube
Merge pull request #11 from kpartlow/master

Object[] by way of GroovyExpression vs. array types.