Correct grammar on Mailer generator -- passES. Working on enhancing...

Correct grammar on Mailer generator -- passES. Working on enhancing conventional readability in README and USAGE files.

actionmailer/lib/rails/generators/mailer/USAGE

 Description:
 ============
-    Stubs out a new mailer and its views. Pass the mailer name, either
+    Stubs out a new mailer and its views. Passes the mailer name, either
     CamelCased or under_scored, and an optional list of emails as arguments.
 
     This generates a mailer class in app/mailers and invokes your template