Escape a literal pound for Markdown

Markdown treats this as an H1 otherwise.

docs/SubmittingPatches

@@ -176,7 +176,7 @@ submitted to JIRA.
 
 You can also reach us on freenode.net at:
 
-> #freeswitch-dev
+> \#freeswitch-dev
 
 Finally, feel free to join us in our weekly conference call.  Many of
 the core developers are often on the call and you'll have an