Fix non-https routes

[rdohms]

Now that we switched over to HTTPS, we need to fix these:

• Photos from Meetup.com, examples:
  • http://photos4.meetupstatic.com/photos/event/1/b/6/highres_432600438.jpeg
  • http://photos2.meetupstatic.com/photos/member/7/c/6/8/thumb_260011848.jpeg
• Sponsor Logos, examples:
  • http://photos1.meetupstatic.com/photos/sponsor/6/a/8/8/iab120x90_2487272.jpeg
  • http://photos4.meetupstatic.com/photos/sponsor/8/0/e/0/iab120x90_1172992.jpeg
• Google Maps: http://maps.google.com/maps/api/js?sensor=false
• Google Fonts: http://fonts.googleapis.com/css?family=PT+Sans:400,700,400italic,700italic (Found in: https://php.amsterdam/css/amsterdamphp.css)