Add a slime-shortcut to Quickload systems.

[daimrod]

I use the following snippet to add a slime-shortcut which works like
,l but it makes possible to quickload both ASDF and Quicklisp systems.

It uses ido-completing-read but it can be replaced by completing-read
without problem.

    ;;; Quickload a system
    (defslime-repl-shortcut slime-repl-quickload
      ("quickload" "+ql" "ql")
      (:handler (lambda ()
                  (interactive)
                  (let* ((system-names
                          (slime-eval '(cl:nunion
                                        (swank:list-asdf-systems)
                                        (cl:nunion
                                         (cl:mapcar 'ql-dist:name
                                                    (ql:system-list))
                                         (ql:list-local-systems)
                                         :test 'cl:string=)
                                        :test 'cl:string=)))
                         (default-value (slime-find-asd-file
                                         (or default-directory
                                             (buffer-file-name))
                                         system-names))
                         (prompt (concat "System "
                                         (if default-value
                                             (format " (default `%s'): " default-value)
                                           ": ")))
                         (system (ido-completing-read prompt
                                                      (slime-bogus-completion-alist system-names)
                                                      nil nil nil
                                                      'slime-system-history
                                                      default-value)))
                    (insert "(ql:quickload :" system ")")
                    (slime-repl-send-input t))))
      (:one-liner "Quickload a system"))