(zmacs-region-stays): No need to define for compiler.

(zmacs-region-stays): No need to define for compiler.

Expand all viper-cond-compile-for-xemacs-or-emacs calls to a featurep test.

Replace obselete frame-local variables with frame-parameters.
(viper-frame-value): New macro.
(viper-set-cursor-color-according-to-state, viper-save-cursor-color)
(viper-get-saved-cursor-color-in-replace-mode)
(viper-get-saved-cursor-color-in-insert-mode)
(viper-get-saved-cursor-color-in-emacs-mode, viper-set-replace-overlay):
Use viper-frame-value for viper-replace-overlay-cursor-color,
viper-emacs-state-cursor-color, viper-insert-state-cursor-color, and
viper-vi-state-cursor-color values.

(viper-set-minibuffer-overlay): Use when rather than if.