[mkgmap-dev] Commit r4896: step 1 of partial merge from mdr2 branch

Version mkgmap-r4896 was committed by gerd on Fri, 11 Feb 2022 step 1 of partial merge from mdr2 branch - don't render natural=coastline as lines, this is rarely useful - don't fill string table and don't create tempFile for strings when calculating global index for gnapsupp. This reduces I/O and peak memory usage. http://www.mkgmap.org.uk/websvn/revision.php?repname=mkgmap&rev=4896