Installing MediaWiki on a Raspberry Pi

Running MediaWiki on a Raspberry Pi could be very useful for demo, training, development, proof-of-concepts, or for small (personal) projects where no (big) server is needed/required.

It could also be used for development countries (training/school environments) where no internet/electricity is available... A Raspberry Pi can easily run for hours/days on a UPS battery; a Raspberry Pi 3 has a built-in Wi-Fi access point available.

=Mediawiki links=
 * Wikipedia Zero
 * Raspberry Pi