[TOOLING] sql queries to remove unused documents and ngrams from database. Usage: use a crontab to execute it every week for instance.

Also, fixed morpheus version: turns out one can unprefix without a
patch to current library.

https://github.com/morpheusgraphql/morpheus-graphql/pull/639#issuecomment-962113983

Merge branch '86-dev-graphql' of ssh://gitlab.iscpif.fr:20022/gargantext/haskell-gargantext into 86-dev-graphql

Also, add "Advanced" endpoint for node list update to update charts.

This is not the optimal solution since it duplicates so much
data. Best would be to add "children" in the node directly.

Dev doc create endpoint

See merge request haskell-gargantext!64