update example dependencies
deps: pin debug
4.2.0
add Contributing.md

Hopefully this will guide some users when posting new issues. Feel free
to close any issues which don't follow the guidelines.
deprecation messages are bright red on TTYs
build: ignore Contributing
update type-is to 1.2.0
fix behavior of multiple app.VERB for the same path

fixes #2116
update connect to 2.16.1
improve proxy trust with ip address list

closes #2099
remove unnecessary test/support/http

backport of 643397ed21fc7086dc5662d1f291beddfbb976ae
build: improve platform portability
build: clean up package file
build: test coverage with istanbul
build: add coverage reporting
update connect to 2.16.2
build: remove lib-cov fork
tests: improve examples/auth tests
update should to 3.3.1
3.7.0