started work on icons section

Once completed this fixes https://github.com/github/primer/issues/1630.

Related

• move package docs to repos: https://github.com/primer/octicons/pull/916
• https://github.com/primer/design/issues/389

Redirects

The following redirects are needed once this PR gets merged

• https://primer.style/octicons/ → https://primer.style/foundations/icons/
• https://primer.style/octicons/guidelines/design → https://primer.style/foundations/icons/design-guidelines
• https://primer.style/octicons/:icon-name → https://primer.style/foundations/icons/:icon-name

Todo

• build:icons needs to be run on build of docs the json from @primer/octicons-react can be used
• ping @rezrah once this PR has been merged to add the redirects
• Archive docs from octicons

Problems

• blob-stream throws errors in the individual icon pages (will try to replace with native stream)
• jsPDF creates an error when gatsby is built