filter_dataset: A function to filter dataset
In angy89/hyQSAR: Hybrid QSAR model

This function allows to filter the features. It first filter features with NA, after it removes features with too many zeros and the ones with high correlation with others.

1	filter_dataset(X, cor_th = 0.95, zero_th = 0.8)

`X`	is the dataset matrix with samples on rows and features on columns.
`cor_th`	is the maximum accepted correlation between couple of features. Default value is 0.95
`zero_th`	is the maximum percentage of zeros accepted in a feature. Default value is 0.8