README is not very informative

[Tim Landscheidt]

Hi,

when viewing EMMS's ELPA entry with M-x list-packages RET,
it displays the README which is not very informative :-):

| Package emms is available.

|      Status: Available from gnu -- Install
|     Archive: gnu
|     Version: 6.2
|     Summary: The Emacs Multimedia System
|    Requires: cl-lib-0.5, seq-0
|    Homepage: https://www.gnu.org/software/emms/
|    Keywords: emms mp3 ogg flac music mpeg video multimedia
|  Maintainer: Yoni Rabkin <yrk@gnu.org>
|      Author: Jorgen Schäfer <forcer@forcix.cx>
| Other versions: 20201105.2351 (melpa).

| Please read the fine manual which is available in the doc
| directory. We do our best to make sure that it's up to date and
| informative.

| [back]

IMHO copying & pasting the "About GNU/Emms" section from the
website would make the most sense.

Tim