Changes from v3.0 to v3.1
header.html
Added the following code for visitor theme change drop down

<td valign="bottom">  <?php print_theme_dropdown(); ?></td>

 ul{
 	padding-left: 15px;
 	padding-right: 15px;
 	margin: 8px;
 }
 .button {
 	width: 60px
 }
 .person_boxNN {
 	background-color: #FFFFFF;
 	border: solid #9CA3D4 1px;
 	}
 .sex_image {
 	height: 9px;
 	width: 9px;
 	margin-right: 3px;
 }
 .selected-option {
 	background-color: #D6E0EA;
 }
 .cal_day {
 	float: left; 
 	font-weight: bold;
 }
 .rtl_cal_day {
 	direction: rtl;
 	float: right; 
 	color: blue; 
 	font-weight: bold;
 }
 .helpstart1 {
 	font-family: Arial, sans-serif;
 	color: Blue;
 	font-size: 14px;
 	font-weight : bold;
 	text-decoration : none;
 }
 .helpstart2 {
 	font-family: Arial, sans-serif;
 	font-size: 12px;
 	font-weight : bold;
 	text-decoration : none;
 }
 #content {
 	margin-left: 1px;
 }
 #footer {
 	clear: both;
 	COLOR: #000000;
 	font-family: times, times new roman, serif;
 	font-size: 12px;
 	width: 99%; 
 }
 .small_inner_block {
 	height: 250px; 
 	overflow: auto;
 	FONT: 10px times, times new roman, serif;
 	text-decoration: none; 
 }
 .block {
 	background-color: #D6E0EA;
 	COLOR: #000000;
 	border: solid #9CA3D4 1px;
 	font-family: Arial, sans-serif;
 	font-size: 12px;
 	vertical-align: top;
 	margin: 1px;
 	padding: 1px;
 }
 #index_title {
	float: left;
 	clear: none;
 	width: 74%;
 }

 #index_main_blocks {
 	clear: none;
 	width: 74%;
 	float: left;
 }
 
 #index_small_blocks {
 	clear: none;
 	width: 25%;
 	float: right;
 }
 
 #random_picture {
 	text-align: center;
 }
 
 #random_picture .small_inner_block {
 	height: 200px;
 }
 
 /*-- pedigree chart specific stylesheets --*/
 #pedigree_chart {
 	position: absolute;
 	top: 175px;
 	left: 0px;
 }
 /*-- pedigree chart rtl specific stylesheets --*/
 #pedigree_chart_rtl {
 	position: absolute;
 	float: right;
 	top: 175px;
 	right: 0px;
 }
 
 /*-- descendancy chart specific stylesheets --*/
 #descendancy_chart {
 	position: absolute;
 	top: 270px;
 	left: 0px;
 }
 /*-- descendancy chart rtl specific stylesheets --*/
 #descendancy_chart_rtl {
 	position: absolute;
 	float: right;
 	top: 270px;
 	right: 0px;
 }
 
 /*-- relationship chart specific stylesheets --*/
 #relationship_chart {
 	position: relative;
 	top: -40px;
 	left: 0px;
 }
 

 $print_stylesheet = $THEME_DIR."print.css";	//-- CSS level 2 print stylesheet to use
 $PGV_USE_HELPIMG = true;		// set to true to use image for help questionmark, set to false to use $pgv_lang["qm"]
 $PGV_SEX_IMG = "male.gif";
 $PGV_SEXF_IMG = "female.gif";
 $PGV_SEXN_IMG = "fe_male.gif";
 $PGV_SMALL_SEX_IMG = "small/male.gif";
 $PGV_SMALL_SEXF_IMG = "small/female.gif";
 $PGV_SMALL_SEXN_IMG = "small/fe_male.gif";
 $PGV_SMALL_SEARCH_IMG = "small/search.gif";
 $PGV_DARROW_IMG = "darrow.gif";
 $PGV_DARROW2_IMG = "darrow2.gif";
 $CHARTS_CLOSE_HTML = true;		//-- should the charts, pedigree, descendacy, etc clost the HTML on the page

 $baseyoffset = 0;	// -- position the entire pedigree tree relative to the top of the page
 $basexoffset = 0;	// -- position the entire pedigree tree relative to the left of the page
 $Dbaseyoffset = 0;	// -- position the entire descendancy tree relative to the top of the page
 $Dbasexoffset = 0;		// -- position the entire descendancy tree relative to the left of the page

	$submenu = array();
	$submenu["label"] = $pgv_lang["viewyear"];
 	$submenu["labelpos"] = "right";
 	$submenu["icon"] = "$PGV_IMAGE_DIR/$PGV_SMALL_CALENDAR_IMG";
 	$submenu["link"] = "calendar.php?action=year";
 	$submenu["class"] = "submenuitem";
 	$submenu["hoverclass"] = "submenuitem_hover";
 	$menu["items"][] = $submenu;