org-agenda: Fix org-agenda-filter-by-tag-refine

* lisp/org-agenda.el (org-agenda-filter-by-tag-refine): Remove command
  because this functionality is redundant with org-agenda-filter-by-tag
  as of 6c6ae99.

Reported-by: Viktor Rosenfeld <v.rosenfeld@gmx.de>
<http://permalink.gmane.org/gmane.emacs.orgmode/104605>

doc/org.texi

@@ -8606,12 +8606,6 @@ Internet, and outside of business hours, with something like this:
 @end group
 @end smalllisp
 
-@orgcmd{\\,org-agenda-filter-by-tag-refine}
-Narrow the current agenda filter by an additional condition.  When called with
-prefix arg, remove the entries that @emph{do} have the tag, or that do match
-the effort criterion.  You can achieve the same effect by pressing @kbd{+} or
-@kbd{-} as the first key after the @kbd{/} command.
-
 @c
 @kindex [
 @kindex ]
@@ -8926,9 +8920,6 @@ agenda items}.
 @vindex org-agenda-tag-filter-preset
 Filter the agenda view with respect to a tag and/or effort estimates.
 
-@orgcmd{\\,org-agenda-filter-by-tag-refine}
-Narrow the current agenda filter by an additional condition.
-
 @orgcmd{<,org-agenda-filter-by-category}
 @vindex org-agenda-category-filter-preset
 

etc/ORG-NEWS

@@ -211,6 +211,8 @@ It replaces the deprecated ~next~ argument to ~org-previous-line-empty-p~.
 It is a faster implementation of ~outline-show-children~.
 
 ** Removed functions
+*** ~org-agenda-filter-by-tag-refine~ has been removed.
+Use ~org-agenda-filter-by-tag~ instead.
 *** ~org-agenda-todayp~ is deprecated.
 Use ~org-agenda-today-p~ instead.
 *** ~org-babel-get-header~ is removed.

lisp/org-agenda.el

@@ -2319,7 +2319,6 @@ The following commands are available:
 (org-defkey org-agenda-mode-map "_" 'org-agenda-filter-by-effort)
 (org-defkey org-agenda-mode-map "=" 'org-agenda-filter-by-regexp)
 (org-defkey org-agenda-mode-map "|" 'org-agenda-filter-remove-all)
-(org-defkey org-agenda-mode-map "\\" 'org-agenda-filter-by-tag-refine)
 (org-defkey org-agenda-mode-map "~" 'org-agenda-limit-interactively)
 (org-defkey org-agenda-mode-map "<" 'org-agenda-filter-by-category)
 (org-defkey org-agenda-mode-map "^" 'org-agenda-filter-by-top-headline)
@@ -7584,12 +7583,6 @@ to switch between filtering and excluding."
 	      (get-text-property (point) 'tags))))
     tags))
 
-(defun org-agenda-filter-by-tag-refine (arg &optional char)
-  "Refine the current filter.  See `org-agenda-filter-by-tag'."
-  (interactive "P")
-  (org-agenda-filter-by-tag arg char))
-(make-obsolete 'org-agenda-filter-by-tag-refine
-	       "use `org-agenda-filter-by-tag' instead." "8.3.4")
 
 (defun org-agenda-filter-make-matcher (filter type &optional expand)
   "Create the form that tests a line for agenda filter.  Optional