Prevent doctrine/inflector from advancing to 1.2.x.

[timcosgrove]

Changes proposed:

• Fix doctrine/inflector on 1.1.x, as 1.2.x requires PHP7

As of 1.2.0 (https://github.com/doctrine/inflector/commits/v1.2.0) doctrine/inflector requires 7.0, rather than 5.6|7.0.

As Acquia has not yet rolled PHP7 out to production environments yet, we probably want to hold ourselves back.

See similar issue in for Laravel: laravel/framework#20214

[timcosgrove]

Apologies. Getting myself set up w/ proper BLT development locally.

[timcosgrove]

Added updated composer.lock, updated w/ composer update doctrine/inflector

[mikemadison13]

FYI I posted about this over on the acquia/lightning space as well: https://github.com/acquia/lightning/issues/411

[timcosgrove]

Yeah. On one hand, this can be resolved by using PHP 5.6 where you run composer update. On the other hand, I would imagine that many people who run BLT at all run Vagrant or Docker locally, which means they can run 5.6 in their vm/image and run whatever locally. You can take the trouble to run composer update in your VM at that point.

We'll probably just ask all our engineers to run 5.6 locally, but I'll leave this PR open for @grasmash to decline or to not decline.