#5758 Update web infrastructure

[Han-Wen Nienhuys]

• Use https for outgoing links throughout

This avoids mixed mode content on https://lilypond.org

• Use https for lilypond.org; As of today, Thu 13 Feb, lilypond.org
  serves on HTTPS.

• Remove mentions of Virginia Tech and webdev.nl

For posterity, this is how lilypond.org was serving before today:

• Jan & Han-Wen are admins of a Google Cloud Platform project

• In the GCP project, we have

• a backend apache-instance-group serving from us-central1-a
• a single VM running apache on in 'apache-instance-group'
• a static IP pointing to the 'apache-instance-group'

Today, I added

• a load balancer 'lilypond', serving on port 80 and 443 of static
  IP 35.206.114.173
• a google-managed certificate for 'lilypond.org', on the load balancer

Then, I changed lilypond.org DNS to point to 35.206.114.173

https://codereview.appspot.com/559470043

[Han-Wen Nienhuys]

perl

https://codereview.appspot.com/559470043

[Anonymous]

Passes make, make check and a full make doc.

[Anonymous]

Patch on countdown for Feb 18th

[Anonymous]

Patch counted down - please push.

[Anonymous]

Update web content
author  Han-Wen Nienhuys <hanwen@lilypond.org>  
    Thu, 13 Feb 2020 14:07:25 +0000 (15:07 +0100)
committer   David Kastrup <dak@gnu.org> 
    Tue, 18 Feb 2020 11:00:12 +0000 (12:00 +0100)
commit  1edb8b3c857fa9c993164123e6f707cad5afb07b