1. Merge from emako/QuickLook.Plugin.TrialOfficeViewer

   1. Convert to .NET type csproj
   2. Add hint of Readonly file is not supported #1500
   3. Update Syncfusion nuget packages to 27.2.5

2. Button to remove readonly file attribute

Full Changelog: 4...5

NB: This plugin is kindly provided by Syncfusion as a ready-to-use black box. I am not able to add any new feature to or fix any bug from the black box. If a feature is unsupported, then it means that - I am neither able and going to fix it. Should any doubt arises, contact Syncfusion.

Update Syncfusion components to version 18.2.0.59.

NB: This plugin is kindly provided by Syncfusion as a ready-to-use black box. I am not able to add any new feature to or fix any bug from the black box. If a feature is unsupported, then it means that - I am neither able and going to fix it. Should any doubt arises, contact Syncfusion.

Update Syncfusion components to version 17.1.0.38.

Do you have MS Office or WPS Office installed? If so, try this out!

Fix failure when previewing PowerPoint files.

Do you have MS Office or WPS Office installed? If so, try this out!

Init release.