Staticman support for OneDev devops platform

[arthef]

At the moment Staticman supports GitHub and GitLab. It would be very useful to have also support for OneDev: https://github.com/theonedev/onedev
which is free, self-hosted alternative to both above.

I am willing to sponsor implementation for this feature.

[arthef]

For anybody interested I have setup a bounty for the implementation: https://www.bountysource.com/issues/99526689-staticman-support-for-onedev-devops-platform