Add Link to Docs on the Demo site

[arndom]

Feature Request

• A link to the docs for the demo site: https://react-joyride.com/

  • The link can only found in the GitHub readme

Possible Solution

• The Link could be placed in the examples' footer:

[alexisruiz96]

This could be great! Actually i was searching it in the demo but it's not included.

[gilbarbara]

Done!