feat: `--color-help` parameter for metadata

Description

Issue

This is the fifth Merge Request from the SVT-AV1-PSY team aiming to integrate our features into mainline SVT-AV1 under the oversight of Hassene Tmar and Faouzi Kossentini. This MR enables a small quality of life CLI flag to print information in Appendix A.2 of the SVT-AV1 User Guide to help with setting color metadata options.

Note that the printed output uses ANSI escape codes, which are supported by most Linux & macOS systems in terminal emulators but may not be supported on Windows. To remedy this, we disable ANSI escape codes when SVT-AV1 is compiled to anything that looks like a Windows target.

Author(s)

Performance impact

• quality
• memory
• speed
• 8 bit
• 10 bit
• N/A

Test set

• obj-1-fast can be found here
• other
• N/A

Merge method

• Allow the maintainer to squash and merge when PR is ready to create a 1-commit to the master branch. The maintainer will be able to fix typos / combine commit messages to create a more readable 1-commit message or use whatever is stated in the 'Description' section
• I will clean up my commits and the maintainer shall use 'rebase and merge' to the master branch