Rendering of `foreground2`

[zstadler]

Several hiking trails in Israel, including the Israel National Trail, use 3-stripe marks, such as this:

Following an advice from Nop, the osmc:symbol tag for the above symbol is green:green:white_right:blue_stripe where

• green is the trail line colour
• green is the background colour
• white_right is the foreground colour
• blue_stripe if the foreground2 colour

It looks like the foreground2 colour is used by the code

waymarkedtrails-shields/wmt_shields/styles/osmc_symbol.py

Lines 90 to 94 in f882596

	# secondary stripe fill
	if self.fgsecondary is not None:
	ctx.set_source_rgb(*self.config.osmc_colors[self.fgsecondary])
	ctx.set_line_width(0.3)
	self.paint_fg_right(ctx)

but neither the map nor the trail's information pane show the center blue stripe for the trail.