"No array to color with" may be downgraded to a log to avoid spamming with the default configuration

[mwestphal]

Describe the bug When opening any file that supports coloring but do not have any data AND using the default config, F3D will tell you:

"No array to color with"

Which is kinda spammy, especially on Windows because it opens a log window.

To Reproduce Steps to reproduce the behavior:

1. Open the file using f3d cow.vtp

How to fix

Use a a debug log instead of a warning log