add partial support for filters, theoretical event support, more work on subscription interface

far too many things in this commit, unfortunately I cannot finish the work without async support, so I think it is better to merge as-is so we avoid big merge effort later
The event api might also have to be changed later, it is far from perfect.
I checked that everything compiles and tests work
Yes, you are wrong :-). Events notification are too be generated by user
with api.
DataChange notification are generated by address space
So this method must be part of api and only on server side.
On Aug 1, 2014 11:40 PM, "Alexander Rykovanov" <notifications@github.com>
wrote:

> In src/server/address_space_addon.h:
>
> > @@ -59,6 +60,11 @@ namespace OpcUa
> >
> >      public: // MonitoredItemsServices
> >        virtual MonitoredItemsData CreateMonitoredItems(const MonitoredItemsParameters& parameters);
> > +      virtual std::vector<StatusCode> DeleteMonitoredItems(const DeleteMonitoredItemsParameters params);
> > +
> > +
> > +    public: // Server internal methods
> > +      virtual void TriggerEvent(NodeID node, Event event);
>
> What is this method for? Who will genegate events?
> I thought this is a part of functionality of addresspace. When data or
> structure is changed then address space sends notifications. Am I wrong?
>
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