gnu: Move Emacs packages to new module.

* gnu/packages/emacs.scm: Move almost all packages from here...
* gnu/packages/emacs-xyz.scm: ...to this new module.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
* gnu/packages/ocaml.scm,
gnu/packages/package-management.scm,
gnu/packages/statistics.scm: Update module references.

gnu/local.mk

@@ -155,6 +155,7 @@ GNU_SYSTEM_MODULES =				\
   %D%/packages/elixir.scm			\
   %D%/packages/embedded.scm			\
   %D%/packages/emacs.scm			\
+  %D%/packages/emacs-xyz.scm			\
   %D%/packages/emulators.scm			\
   %D%/packages/enchant.scm			\
   %D%/packages/engineering.scm			\

gnu/packages/ocaml.scm

@@ -37,6 +37,7 @@
   #:use-module (gnu packages compression)
   #:use-module (gnu packages curl)
   #:use-module (gnu packages emacs)
+  #:use-module (gnu packages emacs-xyz)
   #:use-module (gnu packages flex)
   #:use-module (gnu packages gcc)
   #:use-module (gnu packages ghostscript)

gnu/packages/package-management.scm

@@ -43,7 +43,7 @@
   #:use-module (gnu packages curl)
   #:use-module (gnu packages dbm)
   #:use-module (gnu packages docbook)
-  #:use-module (gnu packages emacs)
+  #:use-module (gnu packages emacs-xyz)
   #:use-module (gnu packages file)
   #:use-module (gnu packages gettext)
   #:use-module (gnu packages glib)

gnu/packages/statistics.scm

@@ -48,6 +48,7 @@
   #:use-module (gnu packages cran)
   #:use-module (gnu packages curl)
   #:use-module (gnu packages emacs)
+  #:use-module (gnu packages emacs-xyz)
   #:use-module (gnu packages gcc)
   #:use-module (gnu packages gtk)
   #:use-module (gnu packages gettext)