Explore: loading project repos using Github PAT

[bobertoyin]

See docs about accessing remote content

[bobertoyin]

A slight issue: trying to load_data during Netlify's build step returns a 403 Forbidden error. Must be some kind of connection error/refusal during the build step. There are two options:

1. See if Netlify's buildbots can be configured to allow HTTP requests (may not be possible)
2. Load GitHub repositories with javascript (can be done, must figure out the default if javascript is disabled)