Alternate polygonToCells algorithm (#785) #1247

Job	Run time
Test Compile clang Debug	4m 8s
Test Compile clang Release	3m 11s
CMake correctness checks	5s
Coverage	5m 9s
Test Compile clang Debug -fsanitize=undefined,float-divide-by-zero -fno-sanitize-recover=undefined,float-divide-by-zero	7m 32s
Test Compile clang Release -fsanitize=undefined,float-divide-by-zero -fno-sanitize-recover=undefined,float-divide-by-zero	5m 15s
Test Compile gcc Debug	5m 8s
Test Compile clang Debug -fsanitize=memory -fno-sanitize-recover=memory	13m 34s
Test Valgrind	12m 50s
Test Compile gcc Release	3m 5s
Test Compile clang Release -fsanitize=memory -fno-sanitize-recover=memory	4m 52s
Test Compile clang Debug -fsanitize=address -fno-sanitize-recover=address	8m 2s
Test Compile clang Release -fsanitize=address -fno-sanitize-recover=address	4m 50s
	1h 17m 41s

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