1.2.0: Added new utility classes + fallback for v2.0 of framework

This update provides to all users working with a v1.x of the framework a fallback to work with the upcoming v2.0 (so that it'll be possible to use the updated version of the components + the upcoming components PRO).

What's changed:
1) We've removed the BEM nomenclature from the utility classes, where we think it wasn't used correctly (e.g., .text--center is now .text-center). We've provided a fallback so that older files won't be affected by the change.
2) Classes that target specific breakpoints now use the .class-name@md nomenclature.

What's changed in details:
- new _util.scss file (utility classes now have their own global file).
- removed _alignment.scss file (flexbox utility classes have been moved to the _util.scss file).
- _grid-layout.scss ->  added new max-width classes + new max-width nomenclature for the CSS variables (it's safe to replace the old file with the new one).
- _icons.scss -> minor updates (it's safe to replace the old file with the new one).
- _shared-styles -> minor updates re: --radius variable.
- _spacing.scss -> removed margin utility classes (now part of the util.scss file).
- _typography.scss -> new text utility classes (it's safe to replace the old file with the new one).
- _visibility -> added new classes (it's safe to swap old file with new one).

Co-Authored-By: Claudia Romano <claudia-romano@users.noreply.github.com>

v1.1.2: Added is and extend utility functions

- Util.js mc;
- Version bump to 1.1.2.

v1.1.1: Version bump to 1.1.1

- Added Accessibility global
- Added .container--adaptive class to update the max-width at specific breakpoints

v1.1.0: Added alpha color function + Version bump to 1.1.0

- Updated _colors.scss with new color mixins
- Added alpha color function

v1.0.7: Version bump to 1.0.7

- Added .link and .reset classes
- Updated Readme file