* implement a first version of events
events are briefly stored as nodes, enabling the developer to easily set attributes. Upon triggering the event the filter is immediately applied
* added copyright
* various fixes for events
proper license, full function names in comments and small improvements to comprehension in tutorial_server_events.c. Added a message for when an EventFiler cant be malloc'd. Name improvement for the lists generated by callForEachChild. Events no longer have a name and description. Declared methods only used in subscription_events.c as static.
* further fixes for events
Rename UA_ENABLE_EVENTS to UA_ENABLE_SUBSCRIPTION_EVENTS. Do not #include <queue.h> in ua_plugin_nodestore.h. Ensure either ChangeNotify or EventNotify are being passed to a monitored item. Traded several pointers for their actual objects. Added constness to the public API. Events can only be enabled together with subscriptions and the full ns0
* Fix problems being caused in check_client_subscriptions
* even more fixes for events
removed useless backslashes for the monitoredItemList declaration, moved comment outside of the define for UA_EVENT_ATTRIBUTES, added UA_EXPORT to the declaration of UA_Server_createEvent and UA_Server_triggerEvent, renamed outId to outEventId, fixed up argument definitions for the functions, moved the generation of the overflow event to server_ns0.c, added catches for NULL as return parameters, EventId is returned in createEvent. Fixed up tutorial.
* solve merge conflicts
* fixup api
