[Material][CalendarView] Make all property values on Setters from VisualStates accessible via ThemeResources.

[ADD-Eugenio-Lopez]

What would you like to be added:

ThemeResources for property values that are currently set directly to Setters in VisualStates.

Uno.Themes/src/library/Uno.Material/Styles/Controls/v2/CalendarView.xaml

Lines 207 to 230 in 1da7240

	<VisualState x:Name="PointerOver">
	<VisualState.Setters>
	<Setter Target="Text.BorderBrush"
	Value="{ThemeResource CalendarViewNavigationButtonBorderBrushPointerOver}" />
	<Setter Target="Text.Foreground"
	Value="{ThemeResource OnPrimaryMediumBrush}" />
	<Setter Target="DownArrowGlyph.Fill"
	Value="{ThemeResource OnPrimaryMediumBrush}" />
	</VisualState.Setters>
	</VisualState>
	<VisualState x:Name="Pressed">
	<VisualState.Setters>
	<Setter Target="Text.Foreground"
	Value="{ThemeResource OnPrimaryLowBrush}" />
	<Setter Target="DownArrowGlyph.Fill"
	Value="{ThemeResource OnPrimaryLowBrush}" />
	</VisualState.Setters>
	</VisualState>
	<VisualState x:Name="Disabled">
	<VisualState.Setters>
	<Setter Target="DownArrowGlyph.Opacity"
	Value="0" />
	</VisualState.Setters>

As you can see, the properties Text.Foreground and DownArrowGlyph.Fill have a general color of ThemeResources but these colors afects all the application style, what you need is to use a concrete ThemeResource like CalendarViewNavigationButtonBorderBrushPointerOver.

You can change the size of the font using properties DayItemFontSize and MonthYearItemFontFamily, but you cannot change the WeekDayName and it's always the same size.

Why is this needed:

It would be very useful since this way you can easily customize the style referring to concrete keys of the ThemeResource and properties from change all values. It would not be convenient to modify the template in any other way.