Restructure and tweaks

[KyivJunta]

Hi there, I've made a bunch of small tweaks that, hopefully, will make themes more coherent. Also, I've reduced code duplication in italic/non italic versions of themes - now they use inheritance:
Night Owl.noitalic.color-theme.json
depends on:
Night Owl.color-theme.json

For now its implemented thru undocumented include property of theme files. Hopefully that will make theme tweaking easier.

Here is a bunch of small tweak, some of them may resolve opened issues:

• Variables (definition, function arguments, etc.) now have coherent coloring
• Object literals and properties now use the same coherent coloring as variables Object color error? #206
• Accessing object properties thru chain now has the same coloring as accessing the properties directly Object colour changes depending on the syntax used to access a property #200
• Slightly switched coloring of the built-ins:
  • built-ins such as console.log, now use coherent function invocation coloring
  • keywords (for of this) now using coherent coloring
• Light theme
  • class type tokens now have distinguishable pinkish coloring
  • built-ins such as console now have distinguishable greenish coloring

Here is screenshots of light/dark themes for comparison. "Before" on the left side.

[sdras]

Sorry, I'm happier with the before than the after :) A big part of the theme is contrast- some of the "inconsistencies" are not to keep keywords the same color but rather make them different in different contexts so that one might see them clearly. You can adjust your own version of the theme with workplace settings shown in the README. The CSS-Tricks article linked up explains the reason for these choices.