Deploy YAML Data Serialization PECL extension

Summary:
Required by tests-prod-environment-behaves-correctly to fetch information
from rOPS pillar configuration (stored in YAML).

Test Plan: Launch a REPL PHP shell like psysh, call yaml_parse()

Reviewers: dereckson

Reviewed By: dereckson

Differential Revision: https://devcentral.nasqueron.org/D1966