Set up Air configuration and formatting

[danielinteractive]

• Establish Air configuration for the project, apply formatting standards.
• Remove unnecessary Date field from the description file, add contributor.
• Update documentation and ignore unnecessary files in the build process.
• Signal the development version with a 9000 suffix.

Note: This PR is contributed under the GPLv3 and will stay under the GPLv3.

[weberse2]

Cool! Thanks.