Update error messages, add man page.
 [rsc] --rw-rw-r-- M 374911 rsc sys 1199 Nov  5 11:47 sys/man/8/statusbar
 [rsc] --rw-rw-r-- M 374911 rsc sys 6025 Nov  5 11:48 sys/src/cmd/aux/statusbar.c
	/n/sourcesdump/2005/1105/plan9/sys/src/cmd/aux/statusbar.c:159,165 - 
	/n/sourcesdump/2005/1106/plan9/sys/src/cmd/aux/statusbar.c:159,165
	  void
	  usage(void)
	  {
	- 	fprint(2, "usage: bargraph [-kt] [-w minx,miny,maxx,maxy] 'title'\n");
	+ 	fprint(2, "usage: aux/statusbar [-kt] [-w minx,miny,maxx,maxy] 'title'\n");
	  	exits("usage");
	  }
	  
	/n/sourcesdump/2005/1105/plan9/sys/src/cmd/aux/statusbar.c:241,247 - 
	/n/sourcesdump/2005/1106/plan9/sys/src/cmd/aux/statusbar.c:241,247
	  
	  	switch(rfork(RFFDG|RFPROC|RFNAMEG|RFENVG|RFNOTEG|RFNOWAIT)){
	  	case -1:
	- 		fprint(2, "bargraph: can't fork: %r\n");
	+ 		fprint(2, "statusbar: can't fork: %r\n");
	  		return -1;
	  	case 0:
	  		break;
	/n/sourcesdump/2005/1105/plan9/sys/src/cmd/aux/statusbar.c:253,259 - 
	/n/sourcesdump/2005/1106/plan9/sys/src/cmd/aux/statusbar.c:253,259
	  	if(srv == 0){
	  		mntsrv = rdenv("/mnt/term/env/wsys");
	  		if(mntsrv == 0){
	- 			fprint(2, "bargraph: can't find $wsys\n");
	+ 			fprint(2, "statusbar: can't find $wsys\n");
	  			return -1;
	  		}
	  		srv = malloc(strlen(mntsrv)+10);
	/n/sourcesdump/2005/1105/plan9/sys/src/cmd/aux/statusbar.c:266,277 - 
	/n/sourcesdump/2005/1106/plan9/sys/src/cmd/aux/statusbar.c:266,277
	  	srvfd = open(srv, ORDWR);
	  	free(srv);
	  	if(srvfd == -1){
	- 		fprint(2, "bargraph: can't open %s: %r\n", srv);
	+ 		fprint(2, "statusbar: can't open %s: %r\n", srv);
	  		return -1;
	  	}
	  	sprint(spec, "new -r %s", win);
	  	if(mount(srvfd, -1, "/mnt/wsys", 0, spec) == -1){
	- 		fprint(2, "bargraph: can't mount /mnt/wsys: %r (spec=%s)\n", spec);
	+ 		fprint(2, "statusbar: can't mount /mnt/wsys: %r (spec=%s)\n", spec);
	  		return -1;
	  	}
	  	close(srvfd);
	/n/sourcesdump/2005/1105/plan9/sys/src/cmd/aux/statusbar.c:280,286 - 
	/n/sourcesdump/2005/1106/plan9/sys/src/cmd/aux/statusbar.c:280,286
	  	cons = open("/dev/cons", OREAD);
	  	if(cons==-1){
	  	NoCons:
	- 		fprint(2, "bargraph: can't open /dev/cons: %r");
	+ 		fprint(2, "statusbar: can't open /dev/cons: %r");
	  		return -1;
	  	}
	  	dup(cons, 0);