Swav improvements

[Atharva-Phatak]

What does this PR do?

Quality checks for implementations of SWAV #839

Couple of points I would like to highlight.

• Right now bolts is focused on standard datasets like CIFAR10, etc but it will be very amazing if we can adapt SSL module for custom tasks.
• The SSL fine tuner is just a normal lightingModule we can remove it and let the user create one according to his/her needs. We will just provide the basic models and functionalities required for implementing SSL tasks.
  These changes will require a substantial rewrite and we can discuss this in further issues.

Fixes part of #839

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[Atharva-Phatak]

I am closing this branch. I believe I made a major bug :). Will add the changes to the new branch.

[mergify]

⚠️ The sha of the head commit of this PR conflicts with #900. Mergify cannot evaluate rules on this PR. ⚠️