EditorConfig: Workaround MSVC2017 bug.

Let's just comment out for now.  Thanks to LunaMoo for investigating.

.editorconfig

@@ -2,7 +2,10 @@
 root = true
 
 [*]
-charset = utf-8
+# Temporarily disabled because MSVC2017 misinterprets as utf-8-bom.
+# TODO: Reinstate once fixed build is released:
+# https://developercommunity.visualstudio.com/content/problem/22922/editorconfig-support-interprets-charset-utf-8-as-u.html
+#charset = utf-8
 indent_style = tab
 insert_final_newline = true
 # Would be nice, but don't want to change files unnecessarily.