Rework htmlxref.cnf

Provide only node keyword and update url for manuals on emacsmirror.
Use identical configuration for all of my packages that come with a
manual.

Author: tarsius

docs/htmlxref.cnf

@@ -1,42 +1,19 @@
 # https://www.gnu.org/software/texinfo/manual/texinfo/html_node/HTML-Xref-Configuration.html
 
-EMACS = https://www.gnu.org/software/emacs/manual
+EMACS  = https://www.gnu.org/software/emacs/manual
+MAGIT  = https://docs.magit.vc
+MIRROR = https://docs.emacsmirror.net
 
-auth		mono	${EMACS}/html_mono/auth.html
 auth		node	${EMACS}/html_node/auth/
-
-ediff		mono	${EMACS}/html_mono/ediff.html
 ediff		node	${EMACS}/html_node/ediff/
-
-elisp		mono	${EMACS}/html_mono/elisp.html
 elisp		node	${EMACS}/html_node/elisp/
-
-emacs		mono	${EMACS}/html_mono/emacs.html
 emacs		node	${EMACS}/html_node/emacs/
 
-
-MAGIT = https://docs.magit.vc
-
-forge		mono	${MAGIT}/forge.html
 forge		node	${MAGIT}/forge/
-
-ghub		mono	${MAGIT}/ghub.html
 ghub		node	${MAGIT}/ghub/
-
-magit		mono	${MAGIT}/magit.html
 magit		node	${MAGIT}/magit/
-
-transient	mono	${MAGIT}/transient.html
 transient	node	${MAGIT}/transient/
-
-with-editor	mono	${MAGIT}/with-editor.html
 with-editor	node	${MAGIT}/with-editor/
 
-
-MIRROR = https://emacsmirror.net/manual
-
-borg		mono	${MAGIT}/borg.html
-borg		node	${MAGIT}/borg/
-
-epkg		mono	${MAGIT}/epkg.html
-epkg		node	${MAGIT}/epkg/
+borg		node	${MIRROR}/borg/
+epkg		node	${MIRROR}/epkg/