[subset] Don't drop hinting info by default

Most people expect hinting to be preserved, and the CFF hint-stripper
is slightly buggy right now.
diff --git a/Lib/fontTools/subset.py b/Lib/fontTools/subset.py
index 382942c..21f92a4 100644
--- a/Lib/fontTools/subset.py
+++ b/Lib/fontTools/subset.py
@@ -1696,7 +1696,7 @@
   no_subset_tables = _no_subset_tables_default
   hinting_tables = _hinting_tables_default
   layout_features = _layout_features_default
-  hinting = False
+  hinting = True
   glyph_names = False
   legacy_cmap = False
   symbol_cmap = False