Update libraries/Session.php

Allow config items to be present in any of the configuration files, not just in config/session.php
Rename config.php into session.php and rename some config variables
Default namespace to blank
Edit README.mkd
Edit README.mkd
Update class phpdoc @author
Remove newline
Merge pull request #1 from Marko-M/master

Allow config items to be present in any of the configuration files, not just in config/session.php