Added configuration system

Ignore-this: 1f5f0c8e6deb7d814ee7e641665437d6

darcs-hash:20090314100711-1e3d8-71f5fd2a99850f49af9a0e2b52ce07a76acea45e
Added configuration datatypes module

Ignore-this: a41f2351c8acf38df8bb384803b94e5a

darcs-hash:20090314100913-1e3d8-7e488d4b5bb4d8a234599f4d576518b438a1b665