[Unix] Create a framework for certbot integration tests: PART 1 (#6578)

* First part

* Several optimizations about the docker env setup

* Documentation

* Various corrections and documentation. Add acme and certbot explicitly as dependencies of certbot-ci.

* Correct a variable misinterpreted as a pytest hook

* Correct strict parsing option on pebble

* Refactor acme setup to be executed from pytest hooks.

* Pass TRAVIS env variable to trigger specific xdist logic

* Retrigger build.

* Work in progress

* Config operational

* Propagate to xdist

* Corrections on acme and misc

* Correct subnet for pebble

* Remove gobetween, as tls-sni challenges are not tested anymore.

* Improve pebble setup. Reduce LOC.

* Update acme.py

* Optimize acme ca setup, with less temporary assets

* Silent setup

* Clean code

* Remove unused workspace

* Use default network driver

* Remove bridge

* Update package documentation

* Remove rerun capability for integration tests, not needed.

* Add documentation

* Variable for all ports and subnets used by the stack

* Update certbot-ci/certbot_integration_tests/conftest.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/acme.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/misc.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update tox.ini

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/misc.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/acme.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/utils/acme.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Update certbot-ci/certbot_integration_tests/conftest.py

Co-Authored-By: adferrand <adferrand@users.noreply.github.com>

* Rename to acme_server

* Add comment

* Refactor in a unique context fixture

* Remove the need of CERTBOT_ACME_XDIST environment variable

* Remove nonstrict/strict options in pebble

* Clean dependencies

* Clean tox

* Change function name

* Add comment about coveragerc specificities

* Change a comment.

* Update setup.py

* Update conftest.py

* Use the production-ready docker-compose.yml file for Pebble

* New style class

* Tune pebble to have a stable test environment

* Pin a dependency

tools/dev_constraints.txt

@@ -51,6 +51,7 @@ pytest==3.2.5
 pytest-cov==2.5.1
 pytest-forked==0.2
 pytest-xdist==1.22.5
+pytest-sugar==0.9.2
 python-dateutil==2.6.1
 python-digitalocean==1.11
 PyYAML==3.13