(term-if-xemacs, term-ifnot-xemacs): Delete, replace

(term-if-xemacs, term-ifnot-xemacs): Delete, replace
uses with a simple test.
(term-set-escape-char, term-mode, term-check-kill-echo-list)
(term-send-raw-string, term-send-raw, term-mouse-paste)
(term-char-mode, term-line-mode, term-exec, term-sentinel)
(term-handle-exit, term-read-input-ring)
(term-previous-matching-input-string)
(term-previous-matching-input-string-position)
(term-previous-matching-input-from-input)
(term-replace-by-expanded-history, term-send-input)
(term-skip-prompt, term-bol, term-send-invisible)
(term-kill-input, term-delchar-or-maybe-eof)
(term-backward-matching-input, term-check-source)
(term-proc-query, term-emulate-terminal)
(term-handle-colors-array, term-process-pager, term-pager-line)
(term-pager-bob, term-unwrap-line, term-word)
(term-dynamic-complete-filename)
(term-dynamic-complete-as-filename)
(term-dynamic-simple-complete): Replace one arm ifs with whens or
unlesses.