Merge pull request #828 from franckstauffer/fix

Some UI Fixes
Enhance attribute to permit to choose between picker or select
Fix display of button to add to cart for product variant
Fix drag&drop in structure editor + title button in rich text blocks.
Merge pull request #830 from intportg/dev

Fix drag&drop in structure editor + title button in rich text blocks.
Merge pull request #826 from loiccouturier/master

Enhance attribute to permit to choose between picker or select
re-implement select-model on document-picker
Fix update of VariantGroup to not permit to associate Attribute Group in axis
Add exists and not exists predicate to use in Query
Update Attributes list to not display attributes used by VariantGroup
Add a boolean on the attributes of type groups to define there as Typology

When a group is defined as a typology of product, it will be proposed
in product editor to create it with these attributes
Fix latency on page / topic creation
Merge pull request #831 from inthause/documents

re-implement select-model on document-picker
Merge pull request #832 from loiccouturier/master

Enhance Attributes
Fix latency on page / topic creation (bis)
Merge pull request #833 from inthause/documents

Fix latency on page / topic creation (bis)
Add support for hhvm in build marix