[N/A] Various Cleanup and Feedback from PHCC

[bd-viget]

Summary

This PR incorporates some of the items found during development of PHCC, as well as a few other things addressed in prep for PHCC.

Changelog

• Cleanup Navigation Container component, moved styles into CSS file.
• Remove "Dark" label from colors prefixed with dark-
• Added default logo
• Added Icon Only Button Style
• Added more block support in the Navigation Container component (Site Logo, Buttons, Search, Spacer, and Separator)
• Added new filter to unregister core block styles: acfbt_unregister_block_styles
• PostInstall Enhancements
• Improvements to the Color Palette feature
• Moved some core functionality from the theme to the MU Plugin
• Block Icon Support for the Read More Block
• Disable the Template Part wrapper div when using Template parts
• Implemented ACF Blocks Toolkit API function acfbt() to access functionality from ACF BT.

[nathan-schmidt-viget]

Looks good!
My only thought is how are we changing the buttons/text when they are on a dark background? Are we adding a class dark to the block?

[bd-viget]

Yes, we are still adding the dark- prefix to the slug of the color, however, checking for [class*="has-dark-"] became problematic when an element used a dark text color, adding the class has-dark-black-color, which would produce undesired results. So now we're using css.js to dynamically modify the inner elements' text color when nested in a has-dark-*-background-color element. There is room for improvement with this approach, but will provide more consistent/expected results.