[WIKI] User Guide Intro Page

[rmberriman]

Description
The User Guide main page needs relevant information for future users to use. Currently, it is a blank page with a header, as it was created in the initial Wiki setup.

Or alternatively, this page needs to be removed if no longer deemed necessary.

Acceptance criteria

• A description of the user guide and any necessary information should be on the Wiki here

Related issues
#216

[Jess-Alcantara]

Approved!

[Ravid12]

Approved

[lukethompsxn]

Approved! I think this should be moved in line with the Developer Guide page

[lukethompsxn]

I have updated the User Guide intro page to include a basic overview, sign in information and link to features. I communicated with the assignee of #249 to keep these two pages relatively in line with each other.