InPainting results has default pre-trained flag turned on

[bearpelican]

While trying to repro the in-painting notebook (really cool by the way), I noticed u-net is loading a frozen pre-trained imagenet stem:
learn = unet_learner(dbunch, partial(m, sa=sa), opt_func=opt_func, metrics=[], loss_func=MSELoss())

In this case, the default pretrained flag needs to be specifically turned off:
https://github.com/fastai/fastai2/blob/master/fastai2/vision/learner.py#L183

From my initial tests, it seems to matter.

@JoshVarty

[jph00]

Thanks for noticing! I've set all imagewang results to 'NA' until we have updated numbers.

[JoshVarty]

Thanks for pointing this out. I will re-run and resubmit.