Fixed several locales issues on file import/export

src/admesh/stlinit.cpp

@@ -32,6 +32,8 @@
 
 #include "stl.h"
 
+#include "libslic3r/LocalesUtils.hpp"
+
 #ifndef SEEK_SET
 #error "SEEK_SET not defined"
 #endif
@@ -232,6 +234,7 @@ static bool stl_read(stl_file *stl, FILE *fp, int first_facet, bool first)
 
 bool stl_open(stl_file *stl, const char *file)
 {
+    Slic3r::CNumericLocalesSetter locales_setter;
 	stl->clear();
 	FILE *fp = stl_open_count_facets(stl, file);
 	if (fp == nullptr)