Merge pull request #115 from tbjers/v0.4

MongoDB native driver requires connection URL to support authentication
Version 0.4.3
Expose DB connection errors properly, use delimiter for column names in SQL generator
Version 0.4.4
varchar(256) too big for primary key in MySQL
Version 0.4.5
Updated unit tests to expect varchar(255)
Missed thrown err
Fixed reflexive through-associations
Added fixture for reflexive through-association test
Fix again for Issue #90, problems with eager fetch / join
Stop installing custom postgres
Version 0.4.6
Fix Issue #125 -- named belongsTo associations
Version 0.4.7