Github API authentication needs updating

[dgallichan]

Github have deprecated password access to their API (which is used to automatically update date-of-last-update) so the ruby script update.rb needs updating to take this into account. This is not urgent, as currently the passwordless approach has sufficient quota to process all of the software packages. https://developer.github.com/changes/2019-11-05-deprecated-passwords-and-authorizations-api/

[notZaki]

It looks like passwords will be deprecated on Nov 13 but personal access tokens can be used instead [ref].

If we're lucky, then update.rb won't need to be changed. The only change would be that one of the input arguments will have to be a token instead of a password.