Refactor Providers to use standard model

[steve-winter]

The existing providers have been maintained against the initial Github schema. A refactor to maintain a standard repository schema is necessary to simplify the code base.

[jgadsden]

this is required for issue #9 'Add Gitlab integration', thanks for doing this @steve-winter

[steve-winter]

this is required for issue #9 'Add Gitlab integration', thanks for doing this @steve-winter

Not required for #9, will merge that without the refactor and then address this one. Unless you would prefer to block the PR until this is done?

[jgadsden]

oops, no, my misunderstanding - please go ahead with the PR for #9