PIM-2669: Remove backendStorage property from attribute
PIM-2669: Update CHANGELOG.md
Merge pull request #1340 from akeneo/PIM-2669

PIM-2669: Remove backendStorage property on attribute entities
PIM-2992: Update specs and UT
PIM-2992: Redefine services injecting metric factory
PIM-2992: Update CHANGELOG.md
Update UPGRADE-1.2.md
Update UPGRADE-1.2.md
Merge pull request #1337 from akeneo/PIM-2992

PIM-2992: Use Metric Factory
Merge branch 'master' into fix/update-wsse-authentication