6.2.0

• Fixed: migrations created using kaliop:migration:generate would create yml which was not valid for import, for content
  fields of type eztags

• Improved: it is now possible to set references to the value of content fields which are recursive arrays (only
  1-level arrays were supported previously)

• Improved: in step reference/set, when reference resolving for value is enabled, it will be done recursively if value is an array

• Improved: migration step mail/send learned how to deal with multiple attachment files, using an array for element attach

• Improved: added a cookbook recipe about adding tags to an eztags field

• BC change (for developers extending the bundle): class AbstractExecutor gained a few method and properties, and it lost method parseReferenceDefinition, which was moved to trait ReferenceSetterTrait