Now nilmdb.client, nilmdb.server, nilmdb.cmdline, and nilmdb.utils
are each their own modules, and there is a little bit more of a
logical separation between them.  Various changes scattered throughout
to fix naming (for example, nilmdb.nilmdb.NilmDBError is now
nilmdb.server.errors.NilmDBError).

Reduced usage of "from __future__ import absolute_import" as much
as possible.  It's still needed for the functions in the nilmdb/server
directory to be able to import the nilmdb module rather than the
nilmdb.py script.

This should hopefully ease future packaging a bit.

There's some bug with the testing harness where placing e.g.
  from du import du
in nilmdb/utils/__init__.py doesn't quite work -- sometimes the
module "du" replaces the function "du".  Not exactly sure why;
we work around that by just renaming files so they don't match
the imported names directly.

git-svn-id: https://bucket.mit.edu/svn/nilm/nilmdb@10998 ddd99763-3ecb-0310-9145-efcb8ce7c51f

individual subcommands are still treated as being part of the same
class (and use "self" to refer to the Cmdline class), but they're
different modules now.



git-svn-id: https://bucket.mit.edu/svn/nilm/nilmdb@10850 ddd99763-3ecb-0310-9145-efcb8ce7c51f