add a QR code on the front page so that viewers can load/ bookmark it.

[christinerogers]

thanks to Naghmeh from Ludmer centre for the suggestion:
Given eople at HBM will be standing in front of a monitor and looking at this -- what we really want to do is have them easily capture this link with their phones to read later.

• create qr code pointing to https://aces.github.io/mcin_platforms/#/
• add it at the bottom of Derek's Table of contents, put 3 words above it: "bookmark this page"
• put a screenshot in the PR, especially if PR preview is still broken

@iremkatitas this can be done next week (may 14+) after Steering - thanks.
Derek may be able to help with generating the qr code.