Added some docs to CI core files
diff --git a/system/core/Benchmark.php b/system/core/Benchmark.php
old mode 100644
new mode 100755
index 515550e..a200727
--- a/system/core/Benchmark.php
+++ b/system/core/Benchmark.php
@@ -29,6 +29,11 @@
  */
 class CI_Benchmark {
 
+	/**
+	 * List of all benchmark markers and when they were added
+	 *
+	 * @var array
+	 */
 	var $marker = array();
 
 	// --------------------------------------------------------------------