A strip down version of IPython Configuration system, mostly taken from IPython as is, and not yet totally cleaned.
on particular it does not contain the configuration file loader that have some IPython specific-ness that woudl need to be stripped.
Any object you want to be configurable should inherit from Traitlets.Configurable
and have class attributes that are instance Trailets.
when creating your object, pass it either the config= keyword (that is a
config object) or parent= keyword which is another Configurable object.
Now any value of the form ClassName.trait_name=Value of the Config object will
be set for the object. If you use parent= our can nest config in the form
GrandParent.Parent.Child.attribute=value.