Support for ili9488 displays

[wightmanjr]

Updated const.py and device.py to support ILI9488 displays.

[thijstriemstra]

thanks! couple of things; can you

• add your name to CONTRIBUTING.rst?
• take a look at adding tests?
• find the pdf datasheet and add it to the doc/tech-spec directory?
• check if the docs needs updating?

let us know if you have any questions. See for example https://github.com/rm-hull/luma.lcd/commit/093e53fd753daf6927e22dfe7feca7cd552e7740 for a comprehensive driver addition.

[wightmanjr]

I will work on it. I'm somewhat new to python tests, but will figure it out as I go.

Thanks

[thijstriemstra]

thanks. also see https://github.com/rm-hull/luma.lcd/actions/runs/5232388084/jobs/9451907761#step:9:24 for some linter failures causing the build to fail.

[wightmanjr]

• Added name to CONTRIBUTING.rst

• Updated documentation

• Uploaded ILI9488 datasheet

• Fixed flake errors

• Updated gamma values

• Added tests for ILI9488

[rm-hull]

Aside @thijstriemstra's comments, looks fine to me

[wightmanjr]

Made changes @thijstriemstra requested.

[thijstriemstra]

@wightmanjr there are no new commits since my last review?

[wightmanjr]

Thanks for all the help, it was a great learning experience.