(viper-cond-compile-for-xemacs-or-emacs): Delete macro.

(viper-cond-compile-for-xemacs-or-emacs): Delete macro.
Expand all viper-cond-compile-for-xemacs-or-emacs calls to a featurep test.

Replace obselete frame-local variables with frame-parameters.
(viper-replace-overlay-cursor-color, viper-insert-state-cursor-color)
(viper-emacs-state-cursor-color, viper-vi-state-cursor-color): Only
call make-variable-frame-local on XEmacs.