[mkgmap-dev] Commit r4384: code cleanup using hints from sonarlint, no change in output expected

Version mkgmap-r4384 was committed by gerd on Tue, 03 Dec 2019 code cleanup using hints from sonarlint, no change in output expected - remove dead code, remove redundant specification of type arguments, reformatting - make some fields final - make some methods static code cleanup using hints from sonarlint, no change in output expected - use more lambdas and computeIfAbsent - merge nested if-then clauses - improve formatting http://www.mkgmap.org.uk/websvn/revision.php?repname=mkgmap&rev=4384