Adds fill/stroke parameters to some North Arrows svg images

[agiudiceandrea]

Description

• Adds fill parameter to N,S,E,W letters of NorthArrow_07.svg
• Adds fill/stroke parameters for star and dashed arc of NorthArrow_08.svg
• Adds fill/stroke parameters for star and dashed arc of NorthArrow_09.svg

This allows to change the color of letters, star and dashed arc of the above mentioned north arrow svg images that otherwise remain always black.

Checklist

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[nirvn]

You will also need to add the fill and stroke opacity params.

[nirvn]

@agiudiceandrea , thanks for this contribution.