-[FEATURE] added possibility to set protocol and to remove port from postgresql connection uri (thanks to danielschwartz)
-[REFACTORING] use underscore functions for Utils.isHash (thanks to Mick-Hansen)
-[REFACTORING] removed the 'failure' event and replaced it with 'error'
-[BUG] fixed booleans for sqlite (thanks to vlmonk)
-[FEATURE] added possibility to set protocol and to remove port from postgresql connection uri (thanks to danielschwartz)
-[FEATURE] added possibility to not use a junction table for many-to-many associations on the same table (thanks to innofluence)
-[FEATURE] results of the `import` method is now cached (thanks to janmeier)
-[FEATURE] added possibility to check if a specific object or a whole bunch of objects is currently associated with another object (thanks to janmeier)
