Release/20.27.0

Changelog: https://gitlab.com/gitlab-org/gitter/webapp/-/blob/develop/CHANGELOG.md#20270-2020-06-08

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20.27.0 - 2020-06-08

• Update chat-service.js; operation string parameter in error reporter updated, https://gitlab.com/gitlab-org/gitter/webapp/-/merge_requests/1890
  • Thanks to @zzxoto for the contribution
• Fix create room flow on userhome missing modal styles, https://gitlab.com/gitlab-org/gitter/webapp/-/merge_requests/1892
• Add docs on how to add a Gitter repo readme badge for your room, https://gitlab.com/gitlab-org/gitter/webapp/-/merge_requests/1896
• Fix left-menu toggle icon (size and color), https://gitlab.com/gitlab-org/gitter/webapp/-/merge_requests/1897

Developer facing:

• Fixing README reference to infrastructure documentation, https://gitlab.com/gitlab-org/gitter/webapp/-/merge_requests/1884
• Add .nvmrc file, https://gitlab.com/gitlab-org/gitter/webapp/-/merge_requests/1893
• Change whitelist/blacklist to allowlist/denylist, https://gitlab.com/gitlab-org/gitter/webapp/-/merge_requests/1895