refactor WcfLogReceiverClientFacade, fix backwardscomp

[304NotModified]

Fix backwardscompatiblity with 3.2

The change in NLog 4.0 was unwanted breaking. We need to fix this:

The problem:

• WcfLogReceiverClientFacade won't inherit from ClientBase<...>. But in 3.2.0 WcfLogReceiverClient was returned, and this class did implement ClientBase<...> (which contains 'EndpointandClientCredentailsproperties). Thus: WcfLogReceiverClientFacade should inherit fromClientBase<..>`. But this is difficult to fix. We have to find a good solution for this.

See: #783 and #561

Refactor or remove WcfLogReceiverClientFacade

The class WcfLogReceiverClientFacade introduced in 4.0 (#565), contains unwanted stuff:

• there is a lot of code duplication in the constructors
• every property is implemented with the same if-else constructions
• there are two properties, m_twoWayClient and m_oneWayClient and there is always only one used, hence, it should be one property.
• there are some Hungarian names. e.g. m_oneWayClient should be without the prefix m_.
• ILogReceiverClient and ILogReceiverOneWayClient are almost identical
• WcfLogReceiverClient and WcfLogReceiverOneWayClient are code duplication?

Solutions:

• We should clean this up and create one factory method with do the if (useOneWay) check. It should return an interface and only that interface should be used in the rest of the class.
• Clean up code duplication as much as possible.

code: https://github.com/NLog/NLog/blob/master/src/NLog/LogReceiverService/WcfLogReceiverClientFacade.cs

[MartinTherriault]

I just finished doing it in my fork. Can you take a look? I'm not sure how things should be named. I just used "V2" but I'll change it to something else if you want to.

I restarted from the original code and added the method to the client interface. For the server interface, I inherited the original interface and added the new method. The target kept its parameter to indicate which method to use.

There is however one possibility in which the changes could break old code, it is if someone was inheriting directly the client interface, they would have to implement the new method for the code to compile. I tried to make it work with two client interfaces, but I get errors with the .config file that I have not managed to fix yet.

[304NotModified]

Great!! Just make a (new) PR please. That's easier to discuss.

[304NotModified]

fixed by #874