Use https instead of http

tools/upgrade.sh

@@ -9,7 +9,7 @@ then
   printf '\033[0;32m%s\033[0m\n' '\____/_/ /_/  /_/ /_/ /_/\__, /    /___/____/_/ /_/  '
   printf '\033[0;32m%s\033[0m\n' '                        /____/                       '
   printf '\033[0;34m%s\033[0m\n' 'Hooray! Oh My Zsh has been updated and/or is at the current version.'
-  printf '\033[0;34m%s\033[1m%s\033[0m\n' 'To keep up on the latest news and updates, follow us on twitter: ' 'http://twitter.com/ohmyzsh'
+  printf '\033[0;34m%s\033[1m%s\033[0m\n' 'To keep up on the latest news and updates, follow us on twitter: ' 'https://twitter.com/ohmyzsh'
   printf '\033[0;34m%s\033[1m%s\033[0m\n' 'Get your Oh My Zsh swag at: ' 'http://shop.planetargon.com/'
 else
   printf '\033[0;31m%s\033[0m\n' 'There was an error updating. Try again later?'