Massive refactoring

This commit does some massive refactoring of the Salt source:

  - reclass and all adapters have been changed to support the distribute
    (setuptools) entry-points interface, while they are also runnable
    directly (using `/usr/bin/env python`);

  - reclass and all adapters now use exactly the same approach to
    configuration (sensible defaults + config file + command-line
    options), but inventory/nodeinfo is properly parametrised (e.g.
    top/pillar for Salt);

  - the documentation has been updated accordingly;

  - defaults and constants were factored out into common modules.

Signed-off-by: martin f. krafft <madduck@madduck.net>
diff --git a/reclass.py b/reclass.py
new file mode 100755
index 0000000..a0d8eb8
--- /dev/null
+++ b/reclass.py
@@ -0,0 +1,11 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+#
+# This file is part of reclass (http://github.com/madduck/reclass)
+#
+# Copyright © 2007–13 martin f. krafft <madduck@madduck.net>
+# Released under the terms of the Artistic Licence 2.0
+#
+
+import reclass.cli
+reclass.cli.main()