Merge branch 'docs/ssot_issue_analytics' into 'master'

Edit "Group analytics" for SSOT

See merge request gitlab-org/gitlab-ce!29241

doc/user/group/issues_analytics/index.md

+---
+type: reference
+---
+
 # Issues Analytics **[PREMIUM]**
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab-ee/issues/7478) in [GitLab Premium](https://about.gitlab.com/pricing/) 11.5.
 
-GitLab by default displays a bar chart of the number of issues created each month, for the
-current month, and 12 months prior, for a total of 13 months.
+Issues Analytics is a bar graph which illustrates the number of issues created each month.
+The default timespan is 13 months, which includes the current month, and the 12 months
+prior.
 
-You can change the total number of months displayed by setting a URL parameter. 
-For example, `https://gitlab.com/groups/gitlab-org/-/issues_analytics?months_back=15`
-would show a total of 15 months for the chart in the GitLab.org group.
+To access the chart, navigate to a group's sidebar and select **Issues > Analytics**.
 
-The **Search or filter results...** field can be used for filtering the issues by any attribute. For example, labels, assignee, milestone, and author.
+Hover over each bar to see the total number of issues.
 
-To access the chart, navigate to a group's sidebar and select **Issues > Analytics**.
+To narrow the scope of issues included in the graph, enter your criteria in the
+**Search or filter results...** field. Criteria from the following list can be typed in or selected from a menu:
+
+- Author
+- Assignee
+- Milestone
+- Label
+- My reaction
+- Weight
+
+You can change the total number of months displayed by setting a URL parameter.
+For example, `https://gitlab.com/groups/gitlab-org/-/issues_analytics?months_back=15`
+shows a total of 15 months for the chart in the GitLab.org group.
 
 ![Issues created per month](img/issues_created_per_month.png)
+
+<!-- ## Troubleshooting
+
+Include any troubleshooting steps that you can foresee. If you know beforehand what issues
+one might have when setting this up, or when something is changed, or on upgrading, it's
+important to describe those, too. Think of things that may go wrong and include them here.
+This is important to minimize requests for support, and to avoid doc comments with
+questions that you know someone might ask.
+
+Each scenario can be a third-level heading, e.g. `### Getting error message X`.
+If you have none to add when creating a doc, leave this section in place
+but commented out to help encourage others to add to it in the future. -->