Modify classifier hyperparameter defaults and ranges

[agitter]

Some of our example datasets don't converge with 500 iterations.

@fmu2 do you remember whether these are the only lines that need to be edited to change the default iterations? Do I need to change it in both places or is that redundant?

[agitter]

I'm generalizing this pull request to update other classifiers. The last commit allows up to 50 estimators for the random forest.

@cmilica are there other hyperparamters you recommend modifying?

Once we're done with all the changes, I'd like to do more local testing before merging.

[cmilica]

I think that is the most important one for the upcoming workshop!

[agitter]

These screenshots document the new changes in the software:

Logistic regression now trains to completion on the T cell size_intensity_feature.csv dataset. I'll merge soon if there are no objections.

[agitter]

I also made ml4bio lower case in the window title to be consistent with our latest workshop.