Implemented NavigationRequest.cs, NavigationHandler.cs and MvuParamsPage class for the Navigation.

[cindiam]

Fixes #6

[cindiam]

This is the error when sending the massage to navigate to another page:

fail: Microsoft.AspNetCore.Components.Server.Circuits.CircuitHost[111]
Unhandled exception in circuit 'Njvb2Y6w1RRruFK_Za-TH68nvtfaFr_pnqt7ImTtrZo'.
System.InvalidCastException: Unable to cast object of type 'NavigateTo' to type 'MvuSha
rp.Internal.RequestHandlerWrapper1[MvuSharp.Unit]'. at MvuSharp.Internal.Mediator.SendAsync[TResponse](IRequest1 request, CancellationT
oken cancellationToken) in C:\Users\Cindia\Documents\MvuSharp\src\MvuSharp.Core\Internal\Medi
ator.cs:line 20
at MvuSharp.Internal.Mediator.SendAsync(IRequest request, CancellationToken cancella
tionToken) in C:\Users\Cindia\Documents\MvuSharp\src\MvuSharp.Core\Internal\Mediator.cs:line
26
at CustomGreeting.Core.Question.<>c__DisplayClass3_0.<b__0>d.MoveNext() in C
:\Users\Cindia\Documents\MvuSharp\demo\CustomGreeting.Core\Question.cs:line 37
--- End of stack trace from previous location ---
at MvuSharp.MvuProgram4.MsgLoopAsync(Queue1 msgQueue, CancellationToken cancellati
onToken, IMediator mediator) in C:\Users\Cindia\Documents\MvuSharp\src\MvuSharp.Core\MvuProgr
am.cs:line 92
at MvuSharp.MvuProgram4.DispatchAsync(TMsg msg, CancellationToken cancellationToken ) in C:\Users\Cindia\Documents\MvuSharp\src\MvuSharp.Core\MvuProgram.cs:line 67 at MvuSharp.Blazor.MvuPage4.Dispatch(TMsg msg, CancellationToken cancellationToken)
in C:\Users\Cindia\Documents\MvuSharp\src\MvuSharp.Blazor\MvuPage.cs:line 32
at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletio
n(Task task)
at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask(Task task
ToHandle)

[rglezg]

Looks like you found a bug on registering of non-generic handlers. I've already created #14 for fixing it. In the meantime, I have changed the implementation of NavigationHandler to a function handler for this to work.