Cleaned up newline shortcuts.

I found out that in emacs 24.1 you can use electric-indent-mode instead of rebinding RET. I also added a smart-open-line that will create a newline below your current line. I tried several different keybindings, but not all of them worked in the terminal (S-RET, C-RET). I went with C-o. C-o seemed to be bound to the same functionality as plain RET. If people have heart burn about rebinding C-o, we can find another keybinding.