GFFx v0.4.0 Release Notes

Added two useful functionalities: coverage for calculating breadth of coverage and depth for calculating depth of coverage from BAM/SAM/CRAM or BED
files on a GFF file.

Added a sample functionality for random downsampling of feature groups from each chromosome at equal ratios.

Updated module organization and source code directory layout to conform to the Rust 2024 edition guidelines for module visibility (pub) and path impor
ts.