Well-known AG configuration directories

[Robert Olson]

I'd like to have the AG system define the following configuration 
directories. I realize this is being done now, but these go toward 
documenting & codifying current practice (and providing standard names).

Per-user configuration. This will hold things like the user profile, 
defaults, and a user's certificate repository.

Defaults:
Linux: $HOME/.AccessGrid
Windows has the notion of an Application Data directory. This can be 
retrieved programmatically thusly:

from win32com.shell import shell, shellcon

appData = shell.SHGetFolderPath(0, shellcon.CSIDL_APPDATA, 0, 0)

Per-machine configuration.