cubicweb-rqlcontroller #4456291 Got crashes instead of clean error messages [resolved]

When a reference to a previous RQL request is wrong (empty or multi-line rset), we get a crash instead of a clean error message

prioritynormal
typebug
done in0.2.0
load0.250
load left0.000
closed by#fe2e2cbfdb7d Fix wrong string format in Exception messages
patchFix wrong string format in Exception messages [applied]