Add information connecting to Juliaup to Windows Store Site

Currently all links only lead to Julia itself, and juliaup is not mentioned anywhere. This may be confusing, and makes the possibilities of Juliaup hard to recognize. Maybe a link to this repository, a short description that it also contains juliaup as version manager and a few basic commands could be added to the description?
Is it sufficient to modify storesubmission/pdps/en-us/PDP.xml ?

Start by reviewing storesubmission/pdps/en-us/PDP.xml, which the issue identifies as the possible source for the Windows Store site description. Update the listing to mention Juliaup, connect to this repository, and include a short description and basic commands; confirm the resulting description covers the requested information.

Written by the indexing model from the issue text.