Add keybinding for configurable new window

[ericcornelissen]

As per #96 and this comment I added a keybinding to open a new configurable window. The default binding is Ctrl+Shift+N.

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Alternative design

1] It may be possible to rely less on a parameter (showProfileSelection) in App.xaml.cs, but I personally don't think that's a good idea.

2] There are now two EventArgs (namely CancelableEventArgs and ProfileSelectEventArgs) that basically only hold a boolean value (cancelled and ShowProfileSelection respectively). On the one hand one the naming helps the reader understand the code, on the other hand it you have (albeit simple) duplicate code. I can refactor the EventArgs into a single BooleanEventArgs class like so:

// Current use of CancelableEventArgs
e.Cancelled = true;

// Example of using BooleanEventArgs
cancelable.Value = true;

However, the current approach forces the programmer to be descriptive, whereas the refactor would allow misuse of the EventArgs, like so:

// Misuse of BooleanEventArgs
e.Value = true;

[felixse]

great job 👍

I think a little duplication here is fine, it makes the code more clear this way. I also renamed the new EventArgs to describe the context in which it is used.

[ericcornelissen]

I think a little duplication here is fine, it makes the code more clear this way

Agreed

I also renamed the new EventArgs to describe the context in which it is used.

I wasn't sure about the naming anyway, but this is much better 👌