Document Tor's brand guidelines

The Tor Project's brand has evolved over the past several years and we need to update our brand guidelines to reflect these changes. There are several pieces of the brand that are waiting on completion due to various factors (see color: ux/design#66, illustrations: ux/design#61, updated logo: ux/design#105), however we can get started and create the structure necessary for guidelines and update as needed when these assets are finalized.

For the purpose of creating a foundational set of brand guidelines that we can build upon later, the purpose of this project will not be specific to web or product but overall Tor Project branding.

This structure may evolve as our needs do, but currently these foundational guidelines will cover:

• Color: hierarchy, approved color combinations
• Logos: sizing, clear space, do's and don'ts
• Typography: use, scale, font pairing
• Visuals: application icons, illustrations, phosphor icons, patterns

Some other things I think would be beneficial to explore in the future:

• Photography: we very occasionally include photography into public-facing branding (blog posts, social media), and it could be beneficial to develop guidelines around how we use photography, determine any treatments applied, and develop a library to draw from to better integrate into our brand's personality.
• Brand values: identify what these principles are for The Tor Project to help guide future branding decisions to ensure every aspect of the brand aligns with these foundational beliefs
• Tone/Voice: documenting our voice will ensure consistent tone across visual, written, audio across teams and products
• Patterns: we have a revised onion pattern that is being used on the new websites design, but don't have any other patterns or guidelines around use beyond this instance