[ixpmanager] Upgrades, permissions, sudos, etc.

[Barry O'Donovan]

Marco d'Itri wrote:
> (I think that a more rigorous handling of what is owned by the web 
> server and what is owned by root (and should be owned by a different 
> non-root user instead) is an area that could be improved.)

Web write access is limited to these dirs:

http://docs.ixpmanager.org/install/manually/#file-permissions

 - Barry