PCL support, enhancements for namespace handling, custom collection types

* Fix test case for non-english cultures
* PCL support
  * Disable SerializableAttribute
  * Disable DesignerCategoryAttribute
  * Use XElement instead of XmlElement
* Custom collection types (IList`1 for interface, List`1 for initialization)
* Enhancement of namespace search
  * Namespace can be provided by schema file name
* Update of the client application