PIM-3558 : update the flat value normalizer to order attribute options
for multiselect
Merge pull request #1927 from akeneo/PIM-3558-order-of-options

[SLA] PIM-3558 : update the flat value normalizer to order attribute options
Preparing version 1.2.18
PIM-3556: Fix memory leak on versionning
Merge pull request #1929 from akeneo/PIM-3556-stable

PIM-3556 (stable): Fix memory leak on versionning