Another fix for rhvoice.

config/punctuation/rhvoice-en.conf

@@ -49,6 +49,7 @@ regex;(?i)certificate:===:certifficate
 regex;(?i)lowblow:===:LowBlow
 regex;(?i)nginx:===:EngineX
 regex;(?i)shit:===:shitt
+regex;(?i)slither:===:slitther
 
 [emoticonDict]
 # This dictionary uses regexp when prefixed with "regex;", so be sure to escape anything that would be parsed by regexp, e.g. *, ., ^, $, etc.