 #     + Loop over related special objects adding them to corresponding
 #       collections.
 #     + Clean the applied `specialObjects` namespace.
-# + Export collections (right after collections setup)
+# - Hydrate collections owner (right after collections setup)
 #     + If `link` is array then remove undefined values from it.
 #     + Delete link if it is an epty array or is undefined.
 #     + Remove special objects element from node children.
 #     + Use collection `rel` attribute as a collection name.
 #     + Detect whether current `xpath` points to root node.
 #     + If current node is a root one export collections to target node.
-#     + Otherwise populate collections to node with collection name as a key.
+#     - Otherwise export collections to the current target (should be an API
+#       node instance).
 #     + Clean current namespace of the `_collections` property.
 #
 # ### Hydrate resource links

#     + Save the node instance in `_resources` property with `xpath` base as a
#       namespace and element name as a key.
#     + Set resource link node value to undefined.
# + Resource link export
#     + Detect that current node has a resource links.
#     + Retrive resource links related to `xpath`.
#     + Remove resource link child elements from target node.
#     + If current node is a root one then export corresponding
#       `_resourceLinks` namespace to target.
#     + Otherwise populate the namespace over the node.
#     + Remove related namespace from `_resourceLinks` property.
#
# ### Hydrate resources
#
# + Detect resources.
# - Delegate resource hydration to other hydrator instance.
# + Replace node value with hydrated resource.
#
# ### Hydrate actions

# ### Hydrate top level element attributes
#
# - Save attributes in corresponding property if existed.
#
# ### General tasks
#
# - If current node is an owner of collections, resource links or actions
#   (except the case when the node is a resource)then an API node instance
#   should be created and set as a current target.
# - If current node is a root one then current target should be a hydrator
#   instance target.
# - We should replace node value with current target (if exists).
#
# ### Hydrate collections
#
