Limit package data collection to public GitHub, GitLab and Bintray

[Croydon]

Right now the tools tries to collect information from pretty much everywhere which leads to the insane situation that it needs access rights and tokens from soooo many different sites.

Since the tool should be able to update and gather new information automatically this is unmaintainable as new access tokens would be needed to add manually. Also pretty much all packages will be on public GitHub.com/GitLab.com/Bintray so I see no point in trying to get information from other hosts.