[Openicc] Adding a directory to the OpenIccDirectoryProposal

[Richard Hughes]

In GCM I've switched the default directories to adhere to
OpenIccDirectoryProposal. There's only one thing GCM does that's not
currently mentioned in the proposal, and so I thought I would email
here and get some feedback.

Shared system data (shared to 60 computers by NFS) is stored in /usr/share/color
Per user data is stored in ~/.local/share/color
Per user configuration is stored in ~/.config/color

Now, when GCM sets a profile to be used system wide, it needs to copy
the profile from the users home directory to a shared location (think,
the users home directory is not accessible by other users, and might
even be encrypted so not even accessible by root). We can't copy the
profile to /usr/share/color/icc as this is mounted read only, and is
shared with all computers.

This means we have to copy the generated profile to a _machine_
specific system directory. In GCM at the moment I'm using
/var/lib/color as I think this is the best fit from a FHS point of
view. I would be open to changing this if we can agree on a better
location. If this is a good idea, I would like the location to be
mentioned in the spec.

I'm not sure if it makes sense to add /var/lib/color to the search
path. Maybe it does.

Anyway, comments please. Thanks,

Richard.