Run FIRSTWARNING on a Raspberry Pi
Just tested install-script on Raspberry Pi with positive outcome :-) It's working.
Just one minor complication.
Be sure to add repository for PHP 7 before running the install-script and it will work. (Tested on RPI 2 B+)
Howto add repository for PHP 7:
sudo echo deb http://repozytorium.mati75.eu/raspbian jessie-backports main contrib non-free >> /etc/apt/sources.list
sudo gpg --keyserver pgpkeys.mit.edu --recv-key CCD91D6111A06851
sudo gpg --armor --export CCD91D6111A06851 | sudo apt-key add -