Added Select All toggle

[etroo44]

Hello, I have successfully added the select all toggle to the tracks table.

Closes #252

[NeoCoderMatrix86]

Thanks for your contribution 👍 . I did some checks and would like you to change some minor stuff:

1. The "Select All" checkbox doesn't react to a track beeing unselected. As a user I would expect a state like "partly selected":
   

2. The code can be shortened:
   <Check TValue="bool" CheckedChanged="SelectAllTracks" Checked="selectedTracks.Any()" />

void SelectAllTracks(bool select)
    {
        if(select)
        {
            selectedTracks.AddRange(Cuesheet.Tracks);
        }
        else
        {
            selectedTracks.Clear();
        }
    }

3. The method "SelectAllTracks" should be starting with "On", for example "OnSelectAllTracksChanged".

If you could edit these things, I will include the pull request. I would be happy to see more contributions from you, so if you want, have a look around the issues ;).

[etroo44]

Sure no problem, I'll fix it and create a new pull request.

[etroo44]

Hey, I changed the Select All functionality as you wanted and fixed some bugs, you forgot to remove a track from the selectedTracks list when removing a track from Cuesheet.Tracks in some places.

[NeoCoderMatrix86]

Thanks for your contribution and the fixes in code! I really appriciate this :).

What I am missing is the feature of the new select all, that not all tracks are selected. I wasn't clear I see, so I have a screenshot here from blazorise examples:

The example can be found here: https://bootstrap5demo.blazorise.com/tests/datagrid

This should be included and then the feature is done :).

[etroo44]

Okay, no problem. I hope everything is now as you wanted.

[NeoCoderMatrix86]

Thanks for your contribution, now everything works fine. Also thanks for fixing bugs, I'll look forward for more contributions from you :).