tdf#128463: Make SetCellColor python example actually do sth

The previous one, when run from within the application, gives a
runtime exception.

This commit rewrites this example to:
1. Hide the private function from the UI;
2. Create a new blank Calc file instead of operating directly in the existing file;
3. Set cell colors to draw a "LO" picture in the sheet.
4. Added docstrings and API reference links.

Change-Id: I120a3ede0629a5657fec18f1b0909dfc4bc7ad1c
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/104720
Tested-by: Noel Grandin <noel.grandin@collabora.co.uk>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

0 files changed, 0 insertions, 0 deletions