Move unitpicker to grafana/ui

Fix Datasource Update to no User/Password

Add gicon-shield to sidemenu class

Closes #15591

Fixed scrolling issue that caused scroll to be locked to bottom

* Moved Server Admin and children to separate menu item on Side Menu

* Removed style guide after PR comments

* fix: Viewers with viewers_can_edit should be able to access /explore #15773

* refactoring initial PR a bit to simplify function and reduce duplication

Fix for leaving playlist mode

Fixed scrolling issue that caused scroll to be locked to the bottom of a long dashboard, fixes #15712

Hide time info switch when no time options are specified

Updated react select fork to 2.4.1

In error popup, fixes bug so that string errors are shown again. Fixes #15782

* Fixed #15682 

* fix: Add hideTimeOverride to state since we need to control the Switch

* fix: Back the maxDataPoints change, we need to keep it as a string

Co-authored-by:johannes.schill@polyester.se

fix: limit access to org admin and alerting pages

Rename PanelEditorProps.onChange to onOptionsChange 

use replaceVariables rather than onInterpolate

* Fixed url of back button in datasource edit page, when root_url configured

* Update snapshots

* Use app config directly in ButtonRow instead of passing datasources page URL via prop

* Snapshots update

docs: howto for recreating our debian repositories.

Add #15752 in CHANGELOG