Require the New Relic PHP agent.

[DFurnes]

What's this PR do?

This pull request requires the ext-newrelic extension in Longshot, so we can get this set up properly on Heroku (which has some frustrating gotchas when using the add-on as we've done elsewhere, described in DoSomething/infrastructure#59).

This will now require the New Relic agent to be installed on our locals as well (since Composer checks for ext-* on installs), which is probably a good idea for dev-prod parity anyways. Add in Homestead's after.sh & run a homestead provision (will update docs as well!):

# Install New Relic agent:
sudo sh -c "echo 'deb http://apt.newrelic.com/debian/ newrelic non-free' > /etc/apt/sources.list.d/newrelic.list"
wget -O- https://download.newrelic.com/548C16BF.gpg | sudo apt-key add -
sudo apt-get update

sudo DEBIAN_FRONTEND=noninteractive apt-get -y install newrelic-php5

How should this be reviewed?

We can see whether this installs the extension as it should when deployed to Longshot QA.

Any background context you want to provide?

N/A

Relevant tickets

References DoSomething/infrastructure#49.

Checklist

• Tested on Whitelabel.

[katiecrane]

yay for NewRelic!

[sheyd]

Ugh, the module is still newrelic-php5 🙄.

[DFurnes]

Haha yeah that threw me for a loop, so silly. 🙃

[DFurnes]

Confirming this gets included on builds now!

-----> Installing platform packages...
       - php (7.1.24)
       - ext-gd (bundled with php)
       - ext-mbstring (bundled with php)
       - ext-newrelic (8.3.0.226)
       - nginx (1.8.1)
       - apache (2.4.37)

[DFurnes]

Ah, a gotcha:

Nov 28 14:53:52 longshot-qa app/queue.1: 2018-11-28 19:53:52.488 +0000 (1572 1572) info: New Relic 8.3.0.226 ("carrot" - "56d5a21db092") [daemon='@newrelic-daemon'  php='7.1.24' zts=no sapi='cli'  pid=1572 ppid=1571 uid=36386 euid=36386 gid=36386 egid=36386 backtrace=yes startup=agent os='Linux' rel='4.4.0-1031-aws' mach='x86_64' ver='#34-Ubuntu SMP Tue Sep 25 09' node='a881bd6a-ed58-450d-9d27-138f56a5a52a'] 
Nov 28 14:53:53 longshot-qa app/queue.1: 2018-11-28 19:53:52.488 +0000 (1572 1572) warning: A global default license has not been set or has invalid format. Please add a 'newrelic.license' key in the global php.ini or in the newrelic.ini file, or ensure that a valid license is provided on a per-virtual host or per-directory basis. 

The environment variables were used in the Heroku buildpack to customize how the New Relic agent works (they're not standard). Looking into how we can do this without needing a newrelic.ini in the repo...