Don't try to save files when you don't have the permissions to do so
Quote buffer-file-name in prelude-open
Simplify prelude-rename-file-and-buffer
Merge remote-tracking branch 'upstream/master'

* upstream/master:
  Simplify prelude-rename-file-and-buffer
  Quote buffer-file-name in prelude-open
  Don't try to save files when you don't have the permissions to do so