Render the contours for depth below three meters in steps of 0.5 meter lines

[Krillle]

While the rendered contour lines are quite good for sea areas already, there are two aspects which make them inappropriate for inland waters. Inland waters have much smaller range of depth and usually you have way less water beneath the keel. Inlands water depths of two meters can be considered as safe, while at sea one would not trust anything below at least five meters:

Problem: The contours currently are rendered in steps of 2, 5 and 10 meters

• At inland waters the depth below 2 meters are the relevant areas to know about for safe navigation
• Compare to the navionics crowd sourced Sonar charts [1]

Solution: Render the contours for depth below three meters in steps of 0.5 meter lines

[1] https://webapp.navionics.com/#boating@15&key=m%7Dj_Im%7ChqA