lisp/desktop.el (desktop-restore-frames): Change default to t.

lisp/desktop.el (desktop-restore-frames): Change default to t.
(desktop-restore-in-current-display): Now offer more options.
(desktop-restoring-reuses-frames): New customization option.
(desktop--saved-states): Doc fix.
(desktop-filter-parameters-alist): New variable, renamed and expanded from
desktop--excluded-frame-parameters.
(desktop--target-display): New variable.
(desktop-switch-to-gui-p, desktop-switch-to-tty-p, desktop--filter-tty*)
(desktop--filter-*-color, desktop--filter-minibuffer)
(desktop--filter-restore-desktop-parm, desktop--filter-save-desktop-parm)
(desktop-restore-in-original-display-p): New functions.
(desktop--filter-frame-parms): Use new desktop-filter-parameters-alist.
(desktop--save-minibuffer-frames): New function, inspired by a similar
function from Martin Rudalics.
(desktop--save-frames): Call it; play nice with desktop-globals-to-save.
(desktop--restore-in-this-display-p): Remove.
(desktop--find-frame): Rename from desktop--find-frame-in-display and add
predicate argument.
(desktop--make-full-frame): Remove, integrated into desktop--make-frame.
(desktop--reuse-list): New variable.
(desktop--select-frame, desktop--make-frame, desktop--sort-states):
New functions.
(desktop--restore-frames): Add support for "minibuffer-special" frames.