1. Renames color names in palette. Using names such as "primary" and
"secondary" that are in consistent with designs such as material,
bootstrap and metro UI palettes. It adds `color-` prefix on color
variables in line with Vue Design System.
2. Introduces necessary changes to follow the system color system
everywhere without using any other color:
- It changes tooltip background from black to darker primary
colors.
- It overrides unset styles from tree component
- It ensures footer has same color as top menu.
3. Removes opacity CSS changes to have better control on choices. To
achieve that:
- It introduces new "light" variants of main colors
- It switches to colors with different variants (e.g. in Dialogs it
uses primary color as button as it has variants that can be
activated on hover meanwhile on-surface color is single).
4. Styles a tags (anchor elements) globally for consistency
