Feature request: Add ability to add help text/link to widget

[garrettjstevens]

This came up during an Apollo meeting today. There was a request to add some way to add some help text and possibly a link to docs to a widget. This could especially be nice for external plugins so that developers can add help there for users who want to learn more about what the plugin is displaying. It could possibly be accessible from an icon in the widget header like this: