Rework parseString() using eval()
Rework parseString() using eval()

This change is meant as a way to support Reference objects inside other
objects, for example something like this:

[{'controller': Reference(label = 'DMA2'), 'channel': 0, 'request': 3},
{'controller': Reference(label = 'DMA2'), 'channel': 2, 'request': 3}]

DISTORTEC/distortos,DISTORTEC/distortos,DISTORTEC/distortos,DISTORTEC/distortos