cubicweb #3560541 add rql autocompletion to cubicweb-ctl shell [validation pending]

If readline is available, it would be nice for cubicweb-ctl to provide autocompletions for rql queries.

prioritynormal
typeenhancement
done in3.20.0
load0.500
load left0.000
closed by#c0239d8ae742 [shell] provide autocompletion for rql queries in cubicweb-ctl shell (closes #3560541)
patch[shell] provide autocompletion for rql queries in cubicweb-ctl shell (closes #3560541) [applied]