Merge pull request #4843 from edx/clytwynec/jenkins_how_to_doc

docs/en_us/internal/jenkins/builds.md

docs/en_us/internal/jenkins/jenkins.md

docs/en_us/internal/jenkins/jenkins_images/build_link.png

.../en_us/internal/jenkins/jenkins_images/build_w_params.png

docs/en_us/internal/jenkins/jenkins_images/console_log.png

...rnal/jenkins/jenkins_images/coverage_report_nav_links.png

docs/en_us/internal/jenkins/jenkins_images/failed_shard.png

docs/en_us/internal/jenkins/jenkins_images/failed_tests.png

docs/en_us/internal/jenkins/jenkins_images/passed_tests.png

..._us/internal/jenkins/jenkins_images/pep8_pylint_graph.png

..._us/internal/jenkins/jenkins_images/quality_artifacts.png

...ernal/jenkins/jenkins_images/quality_report_nav_links.png

docs/en_us/internal/jenkins/jenkins_images/quality_shard.png

docs/en_us/internal/jenkins/jenkins_images/started_tests.png

..._us/internal/jenkins/jenkins_images/test_results_link.png

..._us/internal/jenkins/jenkins_images/test_results_page.png

.../internal/jenkins/jenkins_images/unit-bok-choy-shards.png

docs/en_us/internal/jenkins/results.md

docs/en_us/internal/jenkins/troubleshooting.md