Version mkgmap-r3866 was committed by gerd on Sat, 25 Mar 2017
code cleanup: remove undocumented partial implementation of option contours (SRTM data).
The code is not fully working and may cause "There is not enough room in a single garmin map for all the input data." errors as it is difficult to predict the numer of elements added from SRTM data.
The combination of tools like phyghtmap or srtm2osm in combination with splitter is the better choice.