image resize option added

[emrahyldrm]

for decreasing file sizes and creating more readable log files when the image is too big.

[dchaplinsky]

Hello. Thanks for the PR.

Could you check why tests are failing?

[emrahyldrm]

I think there is no relation with this PR, I got same error before this commit.
It seems like an import error because of pyplot which uses numpy. I saw several issues about this error, it can be related with numpy version. According the issue below, numpy 1.15 works well but 1.16 and the CI uses 1.16.

numpy/numpy#14012 (comment)