Simplify Include Directives Hash

[tommy-russoniello]

This simplifies include directives hashes by removing the include_related subhash under each entity. This indirection exists because of an include key that used to be in each hash, but was removed. Since there are never any other keys in the hashes, the include_related subhashes are no longer necessary.

In doing this, I also found (and fixed) a small bug where the processor tries to use an include directives hash as a key for its own subhash instead of the symbol :include_related.

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[scottgonzalez]

@lgebhardt I would like you to confirm something about this change.

@tommy-russoniello asked me why this would have changed but L4389 has another resource that did not change to include data. My explanation for this is that this resource is not a leaf in the things.things.things include, but the other one is, so we did the work of looking up the related things for this one, but not the other.

[lgebhardt]

@scottgonzalez I believe you are correct.

[lgebhardt]

@tommy-russoniello Thanks for cleaning this up.