Improve Null Object generation for WorkType
Rearranging for clarity DataDefinition

Also adding DataDefinition#to_translation_key_fragment with the goal
of moving away from #name_for_application_usage as a fallback method
for converting to a TranslationKeyFragment
An Entity can exist with a Null Work Type
Removing TranslationKeyFragment vestigial check

For past purposes, I was keying off of :name_for_application_usage.
Now I want to shift to exclusively using :to_translation_key_fragment
Adding short-circuit PropertySet conversion

And found a typo
Adding short-circuit for Value conversion

And removing need for feature_helper
Fixing specs that wouldn't run in isolation
Adjusting spec helper names

I was tired of attempting to run specs on `spec/features` by typing
`rspec spec/fe` and attempting to table complete things.
Convering a slow spec to fast spec
Adding time tracking for isolated specs