Code deduplication/tidying

- Move default pagination/sort/search query variable mapping to pagination_head.php
- Remove user_logs.php

invoices.php

@@ -51,22 +51,6 @@
 
   $real_overdue_amount = $total_overdue - $total_overdue_partial;
 
-  //Paging
-  if(isset($_GET['p'])){
-    $p = intval($_GET['p']);
-    $record_from = (($p)-1)*$_SESSION['records_per_page'];
-    $record_to = $_SESSION['records_per_page'];
-  }else{
-    $record_from = 0;
-    $record_to = $_SESSION['records_per_page'];
-    $p = 1;
-  }
-    
-  if(isset($_GET['q'])){
-    $q = mysqli_real_escape_string($mysqli,$_GET['q']);
-  }else{
-    $q = "";
-  }
 
   if(!empty($_GET['sb'])){
     $sb = strip_tags(mysqli_real_escape_string($mysqli, $_GET['sb']));
@@ -74,15 +58,8 @@
     $sb = "invoice_number";
   }
 
-  if(isset($_GET['o'])){
-    if($_GET['o'] == 'ASC'){
-      $o = "ASC";
-      $disp = "DESC";
-    }else{
-      $o = "DESC";
-      $disp = "ASC";
-    }
-  }else{
+  // Reverse default sort
+  if(!isset($_GET['o'])){
     $o = "DESC";
     $disp = "ASC";
   }