GitHub API rate limit stopped install with Composer

[danielhjames]

I found this bug

While following the installation instructions at https://github.com/mpdf/mpdf/blob/development/README.md I saw:

Using version ^7.0 for mpdf/mpdf
./composer.json has been created
Loading composer repositories with package information
Updating dependencies (including require-dev)
  - Installing paragonie/random_compat (v2.0.12)
    Downloading: Connecting...
Could not fetch https://api.github.com/repos/paragonie/random_compat/zipball/258c89a6b97de7dfaf5b8c7607d0478e236b04fb, please create a GitHub OAuth token to go over the API rate limit

This is OK for an individual GitHub user who can create a token, not so useful for a non-interactive install. Apparently, clone commands and 304 responses on the API do not count towards the rate limit: https://developer.github.com/v3/#conditional-requests