Refact/core

[ipmach]

• Refactor CoreComponent to improve code readability.
• Speed unittest.

[ipmach]

@viktorbeck98 please review the PR :)

[viktorbeck98]

Looks good! Only thing I am unsure about is the names. Why did you choose "fit"?
Also, I never really got why we chose _config with underscore, now that you named the other folder _core_op. The files within _config also start with underscore while the ones in _core_op don't. I suggest removing the underscores or at least be fully consistent.

[ipmach]

Looks good! Only thing I am unsure about is the names. Why did you choose "fit"? Also, I never really got why we chose _config with underscore, now that you named the other folder _core_op. The files within _config also start with underscore while the ones in _core_op don't. I suggest removing the underscores or at least be fully consistent.

@viktorbeck98 I renamed the files following previous standard. About the "fit", is because I could not came up with another word that combines the configuration and the training.