Updated include_files and include_db flags to accept negative values

[eugene-manuilov]

Description of the Change

Updated include_files and include_db flags to accept negative values and allow users to control whether files or database are needed via flags. This is important for the new version of wp-local-docker which will use this flags to minimize the number of questions asked by wpsnapshots itself.

Alternate Designs

Benefits

Possible Drawbacks

Verification Process

Run download command using --include_files=yes and --include_db=no flags and it will download only files.

Checklist:

• [x] I have read the CONTRIBUTING document.
• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [ ] I have added tests to cover my change.
• [x] All new and existing tests passed.

Applicable Issues

Changelog Entry

• Changed --include_files and --include_db flags of create, download, pull and push commands to accept negative values.
• Changed --confirm_wp_version_change flag of the pull command to accept negative values.

[tlovett1]

Nice work.