2019-12-20 ssbc.github.io maintenance. 4½ hours.

Fixed broken links and updated stale content. Added redirects for migrated pages and modules. Incorporated changes made in gh-pages to files generated using ssbc-sitegen.

• Updated ssbc-sitegen. %WsFEFnh...
• Updated ssbc/docs. %orerxNY...
• Updated ssb-server/gh-pages. %kUjs1fV...
• Initiated inquiry about ssb-blobs documentation. %gxnr7Cg...
• Migrated repos to git-ssb:
  • https://github.com/ssbc/docs → %DcALX8h...
  • https://github.com/ssbc/ssbc-sitegen → %DZlKKOL...

Previously: %8bm2BEZ... %2UMi2xv... %tEHog9/...