Web-based install/config system

[benoitg]

Add a web based installer/configuration system that
would handle initial configuration of a new
installation, adjusting the file permissions as needed,
showing the status of dependencies, etc.

Almost every option currently in the config file should
now be stored in the database as Network options,
leaving little but the database type, name, username
and password to configure through text files (maybe not
even that...)