help: document color/pager pitfalls on Windows
Even though I figured this out a few weeks ago, I was initially puzzled where
the color went when I upgraded to 4.2 on a different Windows machine. Let's
point users reading the help into the right direction.
I wonder if we should be even more explicit about cmd.exe/MSYS/pager/color
interplay, but at least all of the breadcrumbs are here (I think).
Our full contribution guidelines are in our wiki, please see:
https://www.mercurial-scm.org/wiki/ContributingChanges
If you just want a checklist to follow, you can go straight to
https://www.mercurial-scm.org/wiki/ContributingChanges#Submission_checklist
If you can't run the entire testsuite for some reason (it can be
difficult on Windows), please at least run `contrib/check-code.py` on
any files you've modified and run `python contrib/check-commit` on any
commits you've made (for example, `python contrib/check-commit
273ce12ad8f1` will report some style violations on a very old commit).