cubicweb-conference #1777263 various bugfixes for 0.10.3 [validation pending]

see changesets 325:455b5223b85f and 326:e59e247447c4 and 327:fa29d238115d and 331:cab18811a1cf

prioritynormal
typebug
done in0.10.3
load0.500
load left0.000
closed by<not specified>