PIM-1925 : add new datagrid implementation
PIM-1925 : remove deprecated datagrid manager
PIM-1925 : begin to fix the vendor import (still an issue with
transformers updates)
PIM-1925 : add a vendor manager
PIM-1945 : add a vendor filter (useable in product grid)
PIM-1925 : add crud for custom entity
PIM-1925 : update demo bundle extension
PIM-1925 : update create a custom entity chapter
Merge pull request #12 from akeneo/PIM-1925

PIM-1925 : add new datagrid implementation