This fixes commit 5d5300cd which
automatically changed all 'return' to 'pure' in our code, resulting in
broken SQL etc.

The bug was introduced in

gargantext/haskell-gargantext!177 (diffs)

It caused hyperdata to be updated with whole corpus, serialized, hence
hyperdata inside hyperdata.

This reverts commit a444cb30.

This reverts commit d04cf03b, reversing
changes made to e213a4bf.

This reverts commit b7e406b1.

Read in backend works now, insert and upsert not yet.

[*r*epoSaver*A cEtxicoen]p "rtepioosn/:no deSqlError Id{-0s-tqmlp-Srteatepo1 2=3 8"22-3150013."c,b osrq"l
E[wrixteecNSotdaetSutso r=i eFsa]t a[l(E)r]r
or, sqlErrorMsg = "une instruction insert ou update sur la table \194\171 context_node_ngrams \194\187 viole la contrainte de cl\195\169\n\195\169trang\195\168re \194\171 context_node_ngrams_context_id_fkey \194\187", sqlErrorDetail = "La cl\195\169 (context_id)=(135) n'est pas pr\195\169sente dans la table \194\171 nodes \194\187.", sqlErrorHint = ""}