Reset useful and useless buffers to empty lists

I feel like we should start from scratch on this one and carefully choose the
defaults.

Also this settings is a very personal setting so if we make some buffers
useless we must have a consensus on it. Marking all special buffers starting
with `*` as useless is too aggressive and make Spacemacs less POLA since two
consecutive press on SPC TAB may not revert to the original buffer.

layers/+distributions/spacemacs-base/config.el

@@ -25,9 +25,9 @@
 (setq dired-dwim-target t)
 
 ;; Regexp for useful and useless buffers for smarter buffer switching
-(defvar spacemacs-useless-buffers-regexp '("*\.\+")
+(defvar spacemacs-useless-buffers-regexp '()
   "Regexp used to determine if a buffer is not useful.")
-(defvar spacemacs-useful-buffers-regexp '("\\*scratch\\*")
+(defvar spacemacs-useful-buffers-regexp '()
   "Regexp used to define buffers that are useful despite matching
 `spacemacs-useless-buffers-regexp'.")
 

layers/+email/notmuch/packages.el

@@ -40,9 +40,7 @@
         "aNN" 'notmuch
         "aNi" 'spacemacs/notmuch-inbox
         "aNj" 'notmuch-jump-search
-        "aNs" 'notmuch-search)
-      ;; fixes: killing a notmuch buffer does not show the previous buffer
-      (push "\\*notmuch.+\\*" spacemacs-useful-buffers-regexp))
+        "aNs" 'notmuch-search))
     :config
     (progn
       (dolist (prefix '(("ms" . "stash")

layers/+fun/xkcd/packages.el

@@ -25,5 +25,4 @@
         "h" 'xkcd-prev
         "j" 'xkcd-next
         "k" 'xkcd-prev
-        "l" 'xkcd-next)
-      (push "*xkcd*" spacemacs-useful-buffers-regexp))))
+        "l" 'xkcd-next))))

layers/+lang/clojure/packages.el

@@ -42,7 +42,6 @@
             cider-prompt-save-file-on-load nil
             cider-repl-use-clojure-font-lock t
             cider-repl-history-file (concat spacemacs-cache-directory "cider-repl-history"))
-      (push "\\*cider-repl\.\+\\*" spacemacs-useful-buffers-regexp)
       (add-hook 'clojure-mode-hook 'cider-mode)
       (dolist (x '(spacemacs-jump-handlers-clojure-mode
                    spacemacs-jump-handlers-clojurec-mode

layers/+lang/elm/packages.el

@@ -48,8 +48,6 @@
       (add-hook 'elm-mode-hook 'spacemacs/init-elm-mode))
     :config
     (progn
-      (push "\\*elm\\*" spacemacs-useful-buffers-regexp)
-
       (spacemacs/set-leader-keys-for-major-mode 'elm-mode
         ;; format
         "=b" 'elm-mode-format-buffer

layers/+tools/docker/packages.el

@@ -34,8 +34,7 @@
         "aDP" 'docker-push
         "aDp" 'docker-pause
         "aDr" 'docker-restart
-        "aDs" 'docker-start)
-      (push "\\*docker.+\\*" spacemacs-useful-buffers-regexp)))
+        "aDs" 'docker-start)))
   (with-eval-after-load 'docker-containers
     (evilified-state-evilify-map docker-containers-mode-map
       :mode docker-containers-mode))

layers/+tools/shell/config.el

@@ -14,10 +14,6 @@
 ;; move point to the end of buffer on new output
 (setq comint-move-point-for-output t)
 
-;; Add shell buffers to useful buffers list
-(push "\\*\\(ansi-term\\|eshell\\|shell\\|terminal\.\+\\)\\(-[0-9]+\\)?\\*"
-      spacemacs-useful-buffers-regexp)
-
 ;; Variables
 
 (defvar shell-default-shell (if (eq window-system 'w32)