Basic class fix for calc interval, smarty test page fix

- smarty test page used old variable names
- the interval date calc function was private but should be public
static

www/admin/smarty_test.php

@@ -16,10 +16,10 @@ $CSS_NAME = 'smart_test.css';
 $USE_PROTOTYPE = false;
 $USE_JQUERY = true;
 if ($USE_PROTOTYPE) {
-	$EDIT_JAVASCRIPT = 'edit.pt.js';
+	$ADMIN_JAVASCRIPT = 'edit.pt.js';
 	$JS_NAME = 'prototype.test.js';
-} else if ($USE_JQUERY) {
+} elseif ($USE_JQUERY) {
-	$EDIT_JAVASCRIPT = 'edit.jq.js';
+	$ADMIN_JAVASCRIPT = 'edit.jq.js';
 	$JS_NAME = 'jquery.test.js';
 }
 $PAGE_WIDTH = "100%";

www/lib/CoreLibs/Basic.inc

@@ -1453,7 +1453,7 @@ class Basic
 	// PARAMS: start date, end date
 	// RETURN: overall days, week days, weekend days as array 0...2 or named
 	// DESC  : calculates the days between two dates
-	private function calcDaysInterval($start_date, $end_date, $return_named = false)
+	public static function calcDaysInterval($start_date, $end_date, $return_named = false)
 	{
 		// pos 0 all, pos 1 weekday, pos 2 weekend
 		$days = array ();