DreamVar is not supported, probably not needed

[rcoreilly]

Due to extra complexity in supporting synaptic-level random variables, this has not been implemented for a while and is now officially gone. Can reinstate at some later point as we scale up..

[rcoreilly]

//	DreamVar float32     `viewif:"On" def:"0,0.01,0.02" desc:"extra random variability to add to LWts after every SWt update, which theoretically happens at night -- hence the association with dreaming.  0.01 is max for a small network that still allows learning, 0.02 works well for larger networks that can benefit more.  generally avoid adding to projections to output layers."`