[packagekit] Configuration files for backends

[Valeriy Lyasotskiy]

As more progress on alpm backend is done, it gets too linked with pacman configuration files and Arch Linux repositories, and so, will work well only in Arch. For example, in Arch we can call packages "supported" if they came from "core" or "extra" repository, but any other alpm-based distro can use other names for official repositories. The same with group mapping - if you look at the source of alpm backend, you'll notice that all the group matches are hardcoded.

What I propose is to get some configuration framework, which can be used to get/set config values for backend via PackageKit libs. As far as I know, NetworkManager now uses the similar approach (keyfiles), and previously it was too linked with distribution configuration files.

This can look like pk_backend_get_config_value/pk_backend_set_config_value and the resulting config file can look this way:

[dummy] 
ExampleRepositoryName="livna"
ExampleArch="x86_64"

[alpm]
Supported="core;extra"

[alpm:mapping] 
bmp-plugins="multimedia"
xmms-plugins="multimedia"
base="system"

Any comments on this? :)

-- 
Regards,
Valeriy Lyasotskiy <onestep at irc.lg.ua>