Allow developers to remove the `LogDisplay` trace listener

Currently there's no way to _remove_ the `LogDisplayTraceListener` from the `ExcelDna.Integration` trace source. My expectation is that the code below would remove the (automatically added) `LogDisplay` listener, the same way that it removes the `Default` listener, but in practice it has no effect:

```xml

```

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Start of a File-New Project add-in:


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#### Workaround

The current workaround is to add the `LogDisplay` listener to the configuration, and switch it off (`initializeData="Off"`), which is not the same as removing it:

```xml

```

Actually, I'd expect the code above to throw an exception, given that a listener with the name `LogDisplay` already exists (by default) so unless it's removed first, we should get an error.

This is my expectation of the correct code to override the default `LogDisplay` listener:

```xml

```

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Related documentation
* [Diagnostic Logging](https://github.com/Excel-DNA/ExcelDna/wiki/Diagnostic-Logging#default-configuration)