WWW: Add Initiatives and grant Projects

We have two different types of AboutCode projects that need to be presented on the website:

- "Projects": Ongoing/continuous projects with a GitHub Repository such as scancode-toolkit, purldb, license-expression and many others. Most of these are currently featured in the **AboutCode Projects Overview** section of the homepage.
- "Initiatives": Time-bound projects that can represent grant funded work that will often affect multiple AboutCode repos. We track these in GitHub Projects, but not all GitHub Projects under aboutcode-org are funded from grants. We need to also feature these on the website in the near future.

The key tasks for this issue are:
- [ ] Decide on clear terminology to distinguish between the two types of projects. The names above are provisional for discussion purposes.
- [ ] Design how we want to present Grant projects on the website. The most likely UI is a card grid but this is TBD.
- [ ] Contact each Grantor to confirm if and how they want their Grant project(s) to be listed
- [ ] Design and populate the project cards and where to publish them on the website - e.g. on a new Supporters page that shows both (1) organizations that support AboutCode in general (i.e. Foundation members in the near future) and (2) specific grants

Notes on terminology:
- "Project" and "Repository" have specific meaning in GitHub. A Repository refers to where you store files (including source code). A Project is a way to group and manage a set of issues and pull requests that may affect multiple Repositories. There is an implicit Project for each Repository which is the set of issues and PRs in that Repository.
- "Project" is the most common term to describe both a set of code (and data) and its supporting/maintaining community in the FOSS world. Calling scancode-toolkit, purldb, etc. a Repository instead of a project is poor form because it omits the project community in general and the issues, PRs and other communications among community members.
- As an example, the Sovereign Tech Agency uses the term "project" or "technology" to refer to the objects of their funding - https://www.sovereign.tech/tech.
- NLnet Foundation also uses the term "project" to refer to the objects of their funding - https://nlnet.nl/