- access most globals by their $_XYZ['varname'] name

- fix some code errors and typos (missing $ in front of variable names
and so on)
- fixed a lot of warnings that would have been thrown when error_reporting
is set to show notices (if(isset($variable))) instead of if($variable) for
example)

include/html.php

@@ -197,7 +197,7 @@ function html_frame_start($title = "", $width = "", $extra = "", $innerPad = 5)
 
     if ($width) { $width = 'width="'.$width.'"'; }
 
-$str .= '<table '.$width.' border=0 cellpadding=0 cellspacing=0 align=center>'."\n";
+$str = '<table '.$width.' border=0 cellpadding=0 cellspacing=0 align=center>'."\n";
 
 if ($title)
 {