[Proposal] error msg "no point clouds found" more explicit

[kaesesahnetorte]

If you do not have any valid point cloud files in your specified pointcloud directory, you will get the error msg

labelCloud could not find any valid point cloud files inside the specified folder.

My proposal is to also print the configured path, where the software is looking for the files (e.g. "~/pointclouds").

[ch-sa]

Valid point!

Feel free to open a pull request with the change.

Otherwise I might work on it only in a week or so.

Best,

Christoph