Add Aim integration to PyTorch image classification template

[gorarakelyan]

Summary

Added Aim to PyTorch image classification template as an experiment logger option.

Details

What was added:

• Initialization of aim.Session
• Logging parameters with Aim
• Logging metrics with Aim
• Aim as a logger option in the sidebar
• Experiment name input in the sidebar
• Markdown of how to run UI and link to the full documentation

Checklist

• all tests are passing (see README.md on how to run tests)
• you formatted all code with black
• you checked all new functionality live, i.e. in the running web app
• any generated code is formatted nicely, both in .py and in .ipynb ("nicely" = comparable to the existing templates)
• you added comments in your code that explain what it does
• the PR explains in detail what's new