Added Collection#create, Collection#update and Collection#destroy
Added Collection#create, Collection#update and Collection#destroy

* Use brute force approach for Collection#update and Collection#destroy
  until adapter API updates are completed that allow bulk update and
  delete.
* Added Collection#default_attributes to return the attributes any
  resource created within the Collection will recieve as defaults.
* Return a frozen Array from RelationshipChain#get_children because
  it is currently immutable until it can return a Collection.
* Updated more usage of Module#=== to Object#kind_of

datamapper/dm-do-adapter,basex/ardm-do-adapter