Added links to fix pbi problem /w i386 and amd64 

Line 154
// Check for pbi install and arch type then create symlinks
	if (file_exists('/usr/pbi/vnstat-i386')) { exec("ln -s /usr/local/etc/vnstat.conf /usr/pbi/vnstat-i386/etc/vnstat.conf"); }
	if (file_exists('/usr/pbi/vnstat-amd64')) { exec("ln -s /usr/local/etc/vnstat.conf /usr/pbi/vnstat-amd64/etc/vnstat.conf"); }
Update to frontend 1.5.1; fixes

vnstat_php_frontend-1.5.1:
-replaced the depreciated split() function with explode();
-renamed vnstat_php_frontend-1.5.1-updated

config.php generation:
-added two new static variables for vnstat_php_frontend-1.5.1; $locale and $language
-updated version number

// Unpack and move Vnstat frontend 
	exec("cd ..");
	exec("tar -zxovf /usr/local/pkg/vnstat_php_frontend-1.5.1-updated.tar.gz");
	exec("mv vnstat_php_frontend-1.5.1-updated /usr/local/www/vnstat2");

$locale = "\$locale = 'en_US.UTF-8';";
$language = "\$language = 'en';";

$locale
$language
comments, vnstat conf version #, indents
updated additional package for php front end 1.5.1
Corrected the .abc file paths!

They were pointed at files.pfsense.org before
removed redundant comment
Merge pull request #574 from parawizard/master

Fixes for pbi paths and update to 1.5.1 php front end