[.emacs] Remove mplayer options from stream function

mplayer options are now stored in the mplayer config file so there
isn't any need to pass them in on the command line when calling it
from emacs
[.emacs] Add a function to stream files by passing a buffer region as
the url
[.emacs] Use hyper instead of meta for lambda and fn keybindings
[.emacs] Allow erase-buffer to be called interactively