use x-terminal-emulator rather than xterm

diff -Naur --exclude=debian vile-9.6.orig/statevar.c vile-9.6/statevar.c
--- vile-9.6.orig/statevar.c	2007-11-19 12:26:12.000000000 +1100
+++ vile-9.6/statevar.c	2008-03-16 22:49:47.000000000 +1100
@@ -316,7 +316,9 @@
 get_xshell(void)
 {
     if (x_shell == 0)
-	SetEnv(&x_shell, DftEnv("XSHELL", "xterm"));
+	SetEnv(&x_shell, DftEnv("XSHELL",
+	       "x-terminal-emulator -e " VILE_STARTUP_PATH "/xshell.sh"));
+
     return x_shell;
 }
 
