Merge pull request #845 from intportg/dev

Enable to validate or refuse payment on transactions in BO + fixes
Fix display of attributes axis on variant product.
Enhance block to display detail of document only if it can display on FO
Enhance function exist on document query
Enhance product front office display
Add stock editor for all variant of variant group
Enhance configuration of variant stocks and FO of variant product
Merge pull request #846 from loiccouturier/master

Add variant stocks editor. Enhance FO product display
Enable to auto-validate payment on deferred connectors.
Fix comments and code formatting.
Add handling of substitution-variables attribute on rich-text-input (BO)
This attribute should contain a JSON with one of the following contents:
 - an array (ex: ['subsitution1', 'substitution2', ...]
 - an object (ex: {'substitution1': 'Label1', 'substitution2': 'Label2', ...}
New static method getSubstitutedString on \Change\Stdlib\String to apply substitutions.
Two substitutions (amount and transactionId) available in informations field of deferred connector.