updated guidelines with special character issues

contributing_to_docs/doc_guidelines.adoc

@@ -592,6 +592,27 @@ some code block
 
 . Item 3
 
+=== Invalid formatting
+
+The following are examples of invalid formatting and some resolutions.
+
+*Problem*
+The following is invalid formatting. It is intended to mark up a literal value, `openshift-*`, in bold highlighting.
+Because of the two asterisks, AsciiDoctor does not know which asterisk is the closing tag.
+
+Travis reports _Opening and ending tag mismatch:_.
+
+----
+ *`openshift-*`*
+----
+
+*Solution*
+Use an escape character for the second asterisk or use double asterisks:
+
+++++
+**`openshift-*`**
+++++
+
 ==== Quick Reference
 .User accounts and info
 [option="header"]