LDPCStorage.jl: Utility functions for reading and writing files containing LDPC matrices.

Introduces two new formats" bincsc.json (Based on compressed sparse columns (CSC). Valid json. Replacement for cscmat.) qccsc.json (Based on compressed sparse columns (CSC). Valid json. Store exponents of quasi-cyclic LDPC matrices) Deprecates the old cscmat format. It was a custom text-based format and thus fragile. It's much better to use established formats such as json as a basis. The new formats also make it clearer if a file contains qc-exponents or just a binary ldpc matrix. The format is easily adaptable to non-binary LDPC matrices as well.If you use this software, please cite it as below