Merge pull request #15 from ksoderstrom/master

Fix to add support for String arrays in factories
Release 0.4.1
Advanced reference implementation

Using special names for reference attributes is a limited approach,
which imposes restrictions on models.

monky.ref() function was implemented to overcome this limitation. It can
be used with any attribute and may refer to the specific path or the
document itself.
Merge pull request #16 from toogle/master

Advanced reference implementation
Release 0.4.2