
Preferabely, use SVG as image format.

For bitmap icons, we had the following advise:

All icons to be used should follow this, so that the icons
look alike.

- size 22x22 pixels

- five color:
	#000000000000
	#BFBFBFBFBFBF
	#FFFFFFFFFFFF
	navy
	#B2B2ABABACAC

- two color:
	#BFBFBFBFBFBF
	black

Hint: for editing a bitmap, remove the 'const' with
a text editor.
