docs(CONTRIBUTING.md): proposing words (#4079)

Author: rbalet

CONTRIBUTING.md

@@ -12,6 +12,6 @@ Please feel free to contribute to this project.
 ## Proposing Words
 
 If you have a word you believe belongs in a dictionary, send a pull request.
-For words associated with a particular programming language / environment, they should go in the appropriate dictionary under `dictionaries/<language>`(s).
+For words associated with a particular programming language / environment, they should go in the appropriate dictionary under `dictionaries/<language>/src/<language>.txt`(s).
 For general-purpose words, put them in the closest appropriate `dictionaries/<general-area>`(s).
 See the `README.md` files in those directories for more information.