Docs/panel refactor (#43569)

* new refactored panel docs

* fixed links

* removed xtra sharing link, added links to panel display option tasks

* fixed typo

* add aliases

* incorporate PM feedback

* intermediate commit to resolve merge conflict

* final changes to resolve merge conflicts

docs/sources/panels/specify-thresholds/add-a-threshold.md

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+title = "Add a threshold"
+weight = 20
+aliases = ["/docs/sources/panels/specify-thresholds/add-a-threshold/"]
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+
+# Add a threshold
+
+You can add as many thresholds to a panel as you want. Grafana automatically sorts thresholds from highest value to lowest.
+
+## Before you begin
+
+- [Add a panel to a dashboard]({{< relref "../working-with-panels/add-panel.md" >}}).
+
+**To add a threshold**:
+
+1. Edit the panel to which you want to add a threshold.
+1. On the panel display options, locate the **Thresholds** section.
+1. Click **+ Add threshold**.
+
+   Grafana adds a threshold value and color.
+
+1. Accept the recommendations or edit the threshold.
+   - **Edit color:** To select a color, click the color dot.
+   - **Edit number:** To change the threshold value, click in the field and enter a number.
+1. Select a **Threshold mode**.
+   Threshold mode applies to all thresholds on this panel.
+1. In the **Show thresholds** drop-down, select a threshold display option.
+1. Click **Save**.