BZ1100998 : Discover the <Directory> directive without using Augeas

To discover the <Directory> Apache directive I use the parser as for VirtualHost.
I tested with multiple httpd.*.conf configuration files and several VirtualHost. This seems to work for me.
![rhq-apache-plugin-directories](https://cloud.githubusercontent.com/assets/273896/3076703/5aac1318-e3f5-11e3-90d8-9f52739c5d9a.png)

I hope it goes in the right way.

Regards,
Jérémie.