Support multiple Z in Worksheet: Convert to Matrix: XYZ Gridding and Worksheet: Convert to Matrix: XYZ Log Gridding tools

For XYZZZZ… data, highlight all of them and choose Worksheet: Convert to Matrix: XYZ Gridding… or XYZ Log Gridding….

The result will be put to different matrix objects in same matrix sheet for easy use in future graphs and analyses.

Previously, these tools only accepted one set of XYZ.