Adjust test outputs in test/examples to avoid warnings; fix bug in `expandfirst` handling on Windows#2804

fingolfin wants to merge 3 commits intomasterJuliaDocs/Documenter.jl:masterfrom

mh/clean-and-fix-old-testsJuliaDocs/Documenter.jl:mh/clean-and-fix-old-testsCopy head branch name to clipboard