Refactor the milestone docs

doc/workflow/milestones.md

@@ -3,14 +3,29 @@
 Milestones allow you to organize issues and merge requests into a cohesive group, optionally setting a due date.
 A common use is keeping track of an upcoming software version. Milestones are created per-project.
 
-![milestone form](milestones/form.png)
+You can find the milestones page under your project's **Issues ➔ Milestones**.
+
+## Creating a milestone
+
+To create a new milestone, simply click the **New milestone** button when in the
+milestones page. A milestone can have a title, a description and start/due dates.
+Once you fill in all the details, hit the **Create milestone** button.
+
+>**Note:**
+The start/due dates are required if you intend to use [Burndown charts](#burndown-charts).
+
+![milestone form](milestones/milestone_create.png)
 
 ## Groups and milestones
 
 You can create a milestone for several projects in the same group simultaneously.
-On the group's milestones page, you will be able to see the status of that milestone across all of the selected projects.
+On the group's **Issues ➔ Milestones** page, you will be able to see the status
+of that milestone across all of the selected projects. To create a new milestone
+for selected projects in the group, click the **New milestone** button. The
+form is the same as when creating a milestone for a specific project with the
+addition of the selection of the projects you want to inherit this milestone.
 
-![group milestone form](milestones/group_form.png)
+![group milestone form](milestones/milestone_group_create.png)
 
 ## Special milestone filters