Building better compression together with DivANS

Introduced DivANS, a new framework for structuring compression programs into independent stages (IR generation, IR optimization, and final bitstream conversion) to encourage community innovation and achieve better compression ratios. DivANS uses an LZ-based Intermediate Representation (IR) and Asymmetric Numeral System (ANS) for efficient serialization. Preliminary studies show concrete gains of 2% in compression ratios for many file types.