Pass through any non-ASCII characters from file names into layer names

The Docker build doesn't include proper locale support

CHANGELOG.md

@@ -1,6 +1,10 @@
 ## 1.27.7
 
 * Add an option to produce only a single tile
+* Retain non-ASCII characters in layernames generated from filenames
+* Remember to close input files after reading them
+* Add --coalesce-fraction-as-needed and --coalesce-densest-as-needed
+* Report distances in both feet and meters
 
 ## 1.27.6