v3.0.0-avalonia11-preview3

• Fixes (adds a workaround) runtime theme changing bug
• Add IReadOnlyTheme and change CurrentTheme to use it
• Move some styles to ControlTheme
• Improve some styles to proper work with Avalonia 11
• Make compability styles included by default
• Removed default font size for TextBlock to allow customizing it as part of other controls #208 #186
• Rework ProgressBar styles, add ShowProgressText support
• Fix scroll helper buttons content. #206
• Fixes TabControl style to support TabControlAssist.TabHeaderAlignment #203
• Rework first MenuItems, fix command execution for empty MenuItems #201, reformat MenuItem.xaml
• Fix Ripple effect remains after being simultaneously triggered