provision 6.x-2.0-alpha2

http://community.aegirproject.org/2.0-alpha2

This release features improvements to the IP management mechanisms that were broken in the last alpha1 release. We now manage IP addresses individually, and check if an IP is in use before allowing it to be deleted.

We also finally leave the files alone on spokes in the multi-server model, a long-standing bug in the 1.x series that led to data loss. A lot of work was done to standardize the Nginx configuration to allow for simpler, yet optional, configurations that leave the admin in charge of choosing the optimisation methods.