Engine Twig PHP isn't very flexible with namespaces

[zhawkins]

I am using Pattern Lab Node v5.1.0 and engine-twig-php v5.1.0 on Mac, with Node v11.2.0, using edition-twig (php engine).

Expected Behavior

I should be able to use a twig namespace that's not a directory name and includes / embeds etc should work.

Actual Behavior

When using a twig namespace that's not close to atomic naming conventions (Atoms, Molecules, etc), included partials aren't resolved correctly.

Steps to Reproduce

Within patternlab-config.json add a new namespace with an ID that's not similar to a directory:

          "id": "some_thing",
          "recursive": true,
          "paths": [
            "source/_patterns/05-test"
          ]
        },

Within another pattern twig file, include a new component using this namespace:

{% include "@some_thing/00-test.twig" %}

You should see the warning:

Could not find pattern referenced with partial syntax @some_thing/00-test.twig.
This can occur when a pattern was renamed, moved, or no longer exists but it still referenced within a different template or within data as a link.

I recognize this is a super specific bug that may only impact me and my team so I've got a PR coming. 😄