Default number of items is 3. If this is not the case,
then increase the column width of the summary items
to cater for 2 items plus the date filter.

Imports the files needed for the custom
stage form and adds the EE specific css.

Added stub addStageMixin

The existing stage list items are rendered
in haml, migrating them to vuejs for future
work.

Fix alignment of median value

Test for stage_nav_item.vue

This MR adds the code which displays cycle analytics on a group level.
It reuses the cycle_analytics_bundle file which will later be removed.

This feature is currently behind the analytics feature flag.

Fix plan stage query and the way it is displayed

This is one of many MRs opened in order to improve the overall
internationalisation of the GitLab codebase.

i18n documentation
https://docs.gitlab.com/ee/development/i18n/externalization.html

Reduced the technical debt around our JS flash function by making it a
module that is imported rather than relying on the global function.
The global function still exists mainly for technical debt with how
some requests are being completed, but new JS should import the module
directly.

Also reduces some tech debt in the file by removing the need for jQuery.
Instead Flash is now 100% vanilla JS.

This reverts commit b7c5ca49, reversing
changes made to 9745c98b.