Fix migrate SQL command message to indicate that environment flag wil…

…l pull from config file.

cmd/migrate_sql.go

@@ -46,6 +46,6 @@ Before running this command on an existing database, create a back up!
 func init() {
 	migrateCmd.AddCommand(migrateSqlCmd)
 
-	migrateSqlCmd.Flags().BoolP("read-from-env", "e", false, "If set, reads the database connection string from the environment variable DSN.")
+	migrateSqlCmd.Flags().BoolP("read-from-env", "e", false, "If set, reads the database connection string from the environment variable DSN or config file key dsn.")
 	migrateSqlCmd.Flags().BoolP("yes", "y", false, "If set all confirmation requests are accepted without user interaction.")
 }