CQL2: Move ATS Queries to Standalone Files

As mentioned in #884 there are queries directly in the ATS docs, which would be useful to have standalone for automated testing. For both the queries themselves and for other tools to utilize in their testing.

I have already done a bit of thinking / work on this, but wanted to start this issue to iron out a few details before pushing anything.

The first is file organization. Currently, there are files in cql2/schema/examples/(json|text), to include a few from the clauses. I am not sure it makes sense to be putting even more in there. There are already a fair number of files in there, and as of right now I have ~320 more pulled out.

Would it make sense to have a queries folder directly under standard, and split things up inside there with json and text in each?

standard/
└── queries
    ├── ats_accent
    │   ├── json
    │   └── text
    ├── ats_advanced
    ├── ats_arithmetic
    ├── ats_basic_cql2
    │   ├── test_5
    │   └── test_6
    ├── ats_basic_spatial
    ├── ats_case
    ├── ats_property
    ├── ats_spatial
    ├── ats_temporal
    ├── clause_6
    ├── clause_7
    └── examples

I am not sure if the original standalone examples are as necessary if everything else gets pulled out like this. I have not done an in depth comparison to check yet. I am thinking probably leave them for now and address that later.

Then annex_ats_basic-cql2.adoc#conformance-test-6 is a bit trickier than the rest. Since it is combinations. Eyeballing it, it looks like every part in the table is re-used from Test 5, so the parts can probably be imported again. Then could have the full queries in the corresponding queries directory?

I have text for all of the queries pulled out to files already. As well as json version of all of them. Just need to update the docs to point at them if this all makes sense.

opengeospatial / ogcapi-features

CQL2: Move ATS Queries to Standalone Files #887