Added working PHP file that extracts data from sensorbase

[savage...@gmail.com]

I recently added the file: XML.php to the SVN repository. Feel free
to use the SVN checkout to try and run it. The file show examples of
using simpleXML and cURL to retrieve and parse XML data from a
server. Please look at the file because many of the features will be
reused for our project. In order to successfully run the file you
must:

1. Have access to a PHP5 server. (upload the file to the server)

2. Have "cURL" tool installed which works with PHP5
Install tutorial: http://www.tonyspencer.com/2003/10/22/curl-with-php-and-apache-on-windows/
(you can omit the apache parts)

The file should print out the multi-dimensional array to show what and
how its stored. The PHP file also shows how to access individual
data.