Improve function names

[mirca]

The function names are a bit obscure. I think we can improve them :) Let's also use this function_name style rather than Function_Name.

For example, rather than Ordered_DAG, I would suggest something like solve_regression_ordered_dag.

IsotoneRpkg/R/DAG_isotone_optimization.R

Line 28 in ca9cf88

Ordered_DAG <- function(y, w=rep(1,length(y)), Emat) {