Allow creating an image consisting of a grid of image copies.
Rename the script.
Add documentation.
Make the script work with Python 3.
Improve output message and documentation.
Support images that have an alpha channel.
Refine the setup steps.
Ignore some files and directories.
Allow optional use from a program.
Ensure the pycache directory is ignored.
Show that a directory path can be specified.
Add license information.
Update the usage instructions.
Add tests.
Remove the directive for git to ignore image files.
Add test images.
Merge after rebasing to amend a commit.