Feedback button/link in documentation pages

[epassaro]

I suggest implementing a button (or link) on the bottom of every TARDIS doc page to give feedback (open an issue pointing to the specific page with some pregenerated text).

See the bottom of this page as and example (click it to try and see what it does) https://docs.microsoft.com/en-us/azure/devops/pipelines/get-started/pipelines-get-started?view=azure-devops

sphinx allows to implement small changes in templates so this could be done easily (or not).

Also sphinx and nbsphinx allow to define custom prologs and epilogs in conf.py (probably this approach is easier!).