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.

Now supports "list /foo/bar" in addition to the older "list --path /foo/bar"

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.

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