Add support for CIFAR10 Dataset in the DCGAN Module

[ishandutta0098]

What does this PR do?

This PR adds the CIFAR10 dataset as an option in the DCGAN module and updates the arguments accordingly.

Fixes # (issue)
#971

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📚 Documentation preview 📚: https://lightning-bolts--1046.org.readthedocs.build/en/1046/

[Borda]

is this right with respect to the dataset color distribution?

[aniketmaurya]

the official PyTorch example seem to use the same normalization - https://pytorch.org/tutorials/beginner/blitz/cifar10_tutorial.html

[Borda]

do we have a test for it?

[ishandutta0098]

@Borda @aniketmaurya I read more on it and calculated it as well, the values given in the pytorch docs are an approximation. The exact values are these:
mean: 0.49139968, 0.48215827 ,0.44653124
std: 0.24703233 0.24348505 0.26158768
I checked a number of implementations, found people either approximating the above values to 3 decimal places or using 0.5 values directly.

I will update the code accordingly with the exact values

Reference - https://stackoverflow.com/questions/66678052/how-to-calculate-the-mean-and-the-std-of-cifar10-data