Add better PHP support

[brycekahle]

Remove php 5.5, add 7.2.2
Automatically install composer dependencies and cache them.

Fixes #124
Fixes #102

Co-Authored-By: Arnaud Ligny github@narno.org

[rybit]

we will need to start passing the php version through to these commands.

[brycekahle]

It is just another env var that can be set for a site and passed. No special support needed.

[ArnaudLigny]

Thanks for your great job @brycekahle! 👍

There is a way to contribute to the official documentation? https://www.netlify.com/docs/build-settings/#build-environment-variables

[brycekahle]

@Narno not at the moment. Once this is live, I'll make sure our docs team makes the necessary changes.

[minthemiddle]

@brycekahle How can I find out when it is live? Would be willing to write a tutorial on how to use it.

[brycekahle]

@minthemiddle This is live now.

[minthemiddle]

I just published

“Just commit to git: Build static pages continuously using PHP generators like Jigsaw on Netlify”

https://medium.com/@martin_betz/just-commit-to-git-build-static-pages-continuously-using-php-generators-like-jigsaw-on-netlify-4a3a18327ffa

where I use all the latest improvements on PHP in the build image.

[brycekahle]

Awesome. Thanks for the shout out!

[nelson6e65]

There is a way to set environment variables to customize composer install args? For example, I need to use --ignore-platform-req=php in a specific site