Option to disable automatic conversion between HEX3and HEX6 colors

[erehulka]

Description

Added option to not automatically convert HEX3 colors (#RGB) to HEX6 (#RRGGBB). Corresponding option example has been added to Basics.hbs.

This has been addressed as an issue for quite some time, and unfortunately it wasn't possible to fix it without changing the source code, which wasn't the best idea, if this was installed via npm, or composer.

Everything has been checked and is working fine. If something will come up, I can change and fix this code.

Check list

Please fill this check list before submitting a pull request:

• [x] The build process has been run (npm run build) and does not contain any errors.
• [x] All tests are green after running npm run test.
• [x] New tests have been added or modified for the introduced changes.
• [x] New examples have been added for the newly introduced features.
• [x] All the examples are still working as expected compared to the official website.
• [x] This PR follows all other CONTRIBUTING.md guidelines for Pull Requests.

[erehulka]

Btw I know it is not the most elegant solution, but it doesn’t make big changes to original code, just adds one variable that is passed in ColorItem.js.