A number of docstring fixes

A number of docstring fixes

* lisp/net/dictionary-connection.el (dictionary-connection-p,
  dictionary-connection-read-point, dictionary-connection-process,
  dictionary-connection-buffer, dictionary-connection-set-read-point,
  dictionary-connection-set-process, dictionary-connection-set-buffer,
  dictionary-connection-create-data, dictionary-connection-open,
  dictionary-connection-status, dictionary-connection-close,
  dictionary-connection-send, dictionary-connection-send-crlf,
  dictionary-connection-read, dictionary-connection-read-crlf,
  dictionary-connection-read-to-point): Fix docstring