EPIC: Define a color palette that works with the future plans

[edenhernandez-suse]

The color language of our product needs to be updated for a better user experience and to improve the visual language and reflect better the brand.

• Define the accent color, mainly used for active state https://zube.io/rancher/dashboard-ui/c/9462
• Define the primary color for CTA https://zube.io/rancher/dashboard-ui/c/9463
• Define the color for secondary buttons https://zube.io/rancher/dashboard-ui/c/9464
• Define Semantic colors https://zube.io/rancher/dashboard-ui/c/9383
• Define Grays https://zube.io/rancher/dashboard-ui/c/9461

[edenhernandez-suse]

After @manuelecarlini reviewed it, we decided to test the current palette as a theme in a side branch. We will reuse some colours and see how everything works in order to make the necessary adjustments.

@scures I'll need to work with you on this, I only need a branch with a test theme, I can change the colour variables myself.

[manuelecarlini]

The current state of the art is tracked in the following document
https://xd.adobe.com/view/d111e7be-4ca1-4721-befa-c40fa8e84eac-8442/