Switching between GraphQL and REST engines

[maciekbanas]

As @epijim showcased in #225 the GraphQL is not always the best option even for pulling from GitHub.

My idea to handle 502 error for GraphQL would be to introduce additional method for GitHub Rest Engine to get repos by org (which does not exist for the time-being) - not as default, but supportive in case there comes critical error when pulling via GraphQL.

I am developing this feature on #225 branch. My idea is to set new boolean parameter for the get_repos function (something like supportive) - if it is set to TRUE (after handling errors on the level of GitHost platform) then the REST method is run instead of GraphQL.

@Cotau you are very welcome to give your thoughts.

[maciekbanas]

This is how it could look: