Add donation banner to the Moodle download page

As part of increasing awareness to our donation campaign we want to improve the donation text and links that currently are shown after a user commences the Moodle download via download.moodle.org.

Replace the text pointed at in the screenshot below.

Text to be added:

"Thank you for using Moodle!

We believe that software, especially educational tools, should always be open and free. We rely on our community to support and help us to continuously improve our LMS. Support our developers by making a donation."

Where the word 'donation' should link to our donation page (moodle.com/donations with UTM tracking code).

And below it the attached banner image, also linking to our donation page with UTM tracking code