Adds CNN Trainer

[oke-aditya]

Before submitting

• Was this discussed/approved via a Github issue? (no need for typos and docs improvements)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure to update the docs?
• Did you write any new necessary tests?

What does this PR do?

Fixes #203

Adds a generic CNN Trainer that works for torchvision models.

PR review

I need a bit help to write tests and with the run_cli() method. I'm not sure if they are right.
I have tested this code and it works fine in my repo. It is here

Did you have fun?

Make sure you had fun coding 🙃

[pep8speaks]

Hello @oke-aditya! Thanks for updating this PR.

• In the file pl_bolts/models/__init__.py:

Line 14:1: W391 blank line at end of file

Comment last updated at 2020-10-18 19:32:33 UTC

[codecov]

Codecov Report

Merging #286 into master will decrease coverage by 1.42%.
The diff coverage is 26.01%.

@@            Coverage Diff             @@
##           master     #286      +/-   ##
==========================================
- Coverage   83.87%   82.44%   -1.43%     
==========================================
  Files          91       94       +3     
  Lines        4861     4984     +123     
==========================================
+ Hits         4077     4109      +32     
- Misses        784      875      +91     

Flag	Coverage Δ
#cpu	24.01% <26.01%> (+0.05%)	⬆️
#pytest	24.01% <26.01%> (+0.05%)	⬆️
#unittests	81.90% <25.20%> (-1.44%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
pl_bolts/models/classification/cnn_backbones.py	13.51% <13.51%> (ø)
pl_bolts/models/classification/cnn.py	38.63% <38.63%> (ø)
pl_bolts/models/__init__.py	100.00% <100.00%> (ø)
pl_bolts/models/classification/__init__.py	100.00% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 3187ebe...f013e01. Read the comment docs.

[Borda]

@oke-aditya how is it going here, still wip?

[oke-aditya]

Hey @Borda,

Actually, the code is complete. I need to add tests as well though.

@justusschock said this might need more discussion hence I kept as WIP.

We can discuss on this PR, I guess it is good feature addition though.

This can be used to solve #340 too.

[Borda]

let's close this one for now... :]