[Feature Request]: Add Intro to Storyboards page

[StevenWeathers]

Description

A lot of teams may not know what story mapping is, or know what it is and don't realize the storyboard feature is intended for that usecase. It would be nice to have an intro on the storyboards page to "pitch" the feature.

Describe the solution you'd like

An "elevator pitch" of what a storyboard is and how it's useful to agile teams, could be featured at the top of the page or have a very short intro with a "Learn more" that takes the user to another page for a more in depth guide.

Describe alternatives you've considered

Doing nothing and relying on the current landing page intro.

[StevenWeathers]

For now I've added a description of what story mapping is to the bottom of the storyboards page.