IDE open changed files in diff viewer

Closes #4568

See merge request gitlab-org/gitlab-ee!4789

Docs: refactor doc general guidelines and style guidelines

See merge request gitlab-org/gitlab-ee!4750

Resolve "Geo docs: Second SSH restart only considers ‘ssh’ not ‘sshd’"

Closes #5263

See merge request gitlab-org/gitlab-ee!4990

Update Code Quality example documentation

See merge request gitlab-org/gitlab-ee!4991

CE upstream - 2018-03-16 12:24 UTC

See merge request gitlab-org/gitlab-ee!4998

this reduces the amount of duplicated code between creating a temp tree & a temp file. We just pass a type that dispatches some extra actions for files

this now all goes through the 1 mutationn & the web worker. This keeps all the logic the same for multiple directions

it wasn't previously affecting the performance in any way, however this keeps all the logic of creating folders & files in the worker which we can just post to whenever we need to

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still has a massive bottleneck somewhere

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Resolve "Isolate elasticsearch-using specs"

Closes #4986

See merge request gitlab-org/gitlab-ee!4983

Cache column_exists? for Elasticsearch columns

Closes gitlab-ce#43355

See merge request gitlab-org/gitlab-ee!4987

# Conflicts:
#	doc/ci/examples/README.md
#	doc/ci/examples/sast_docker.md
#	doc/topics/autodevops/index.md

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changed selection background color

added pointer cursor to diff overview

hide viewport display

fix content not resetting when discarded

added comment re. try/catch in dispose

hide diff overview in diff editor