Use asterisks for emphasis- and strong-styles

Given the inconsistent behavior of underscores used within words for
style we should prefer asterisks now that these rules are available.

Author: mcdonnnj

.mdl_config.yaml

@@ -48,3 +48,13 @@ MD035:
 MD046:
   # Enforce the fenced style for code blocks
   style: "fenced"
+
+# MD049/emphasis-style - Emphasis style should be consistent
+MD049:
+  # Enforce asterisks as the style to use for emphasis
+  style: "asterisk"
+
+# MD050/strong-style - Strong style should be consistent
+MD050:
+  # Enforce asterisks as the style to use for strong
+  style: "asterisk"