cleanZtest: Clean Z's columns based on p-values (coefficients or global)
In CorReg: Linear Regression Based on Linear Structure Between Variables

This function cleans the structure of correlations by setting to 0 the coefficients in the sub-regressions that are associated to a p-value below the "pvalmin" threshold.

1	cleanZtest(Z = Z, X = X, pvalmin = 0.05, global = FALSE, bonferroni = FALSE)

`Z`	the binary matrix describing the sub-regression structure (as given by the "structureFinder" function).
`X`	the dataset on which we have the sub-regression structure Z.
`pvalmin`	the threshold on coefficients p-valuesto clean the structure.
`global`	boolean. If TRUE the threshold is only on the F statistic for each sub-regression, not on each coefficients. So it will only remove entire sub-regressions.
`bonferroni`	boolean to use bonferroni correction on the pvalmin parameter to avoid multiple testing issues.