some minor changes for emacs

1. add dictionary-el, from deb package and rebind F1 to it
2. rename _bash_aliases to _aliases, hope there would not be any side
effect
3. add alias `edd` to shutdown emacs daemon smoothly, the correctness is
yet to be tested; a known problem is that it has to run emacsclient
first, which is a bit stupid, so a wrapper function should be written so
that it works just right:-)