Consolidate grails-data-graphql and grails-data-neo4j into grails-data-mapping

[jamesfredley]

Neither of these have been updated for Grails 7, so they will not be built for now, but are being brought over so they can be updated at a later time.

git remote add neo4j git@github.com:grails/grails-data-neo4j.git
git fetch neo4j 
git merge -s ours --no-commit --allow-unrelated-histories neo4j/8.2.x
git read-tree --prefix=neo4j/ -u neo4j/8.2.x
git commit -m "Imported grails-data-neo4j"

git remote add graphql git@github.com:grails/grails-data-graphql.git
git fetch graphql
git merge -s ours --no-commit --allow-unrelated-histories graphql/4.0.x
git read-tree --prefix=graphql/ -u graphql/4.0.x
git commit -m "Imported grails-data-graphql"

[jamesfredley]

The failure is occurring in the 9.0.x branch, so will fix it on another PR first, then rerun this one.

[jdaugherty]

I think @matrei needs to look over this as well.

Only minor nitpicks:

1. Should we update the README.md files to reflect the projects haven't been ported?
2. Should we prefix them with a "grails-data-" or something similar so we can identify these as gorm implementations?

[matrei]

LGTM. grails-data-* directory names could make sense.

[jamesfredley]

I was 50/50 between with and without grails-data-. Since both of you mentioned it I will update. I will also update the readmes before merging.