PIM-2874: Special characters not escaped on filter

Fixed bug with special characters are not well handled in product grid filter
PIM-2874: Fix phpspec in order to fit with changes
PIM-2874: Add spec for filter with special chars
PIM-2874: Updated CHANGELOG.md
PIM-2874: Added behat scenario
PIM-2874: Fix for behat
PIM-2874: FIxed typo in CHANGELOG.md
PIM-2874: Fixed behat
PIM-2874: Fixed code after behat fail
PIM-2874: Fix typo
Update CHANGELOG.md
Clean up behat scenario
Merge pull request #1415 from akeneo/PIM-2874

Pim-2874: Special characters are not well handled in product grid filter