Update README.md

Enrich the Readme

Add and fix some comments

Add inner, outer, cholesky and svd

added documentation to most methods, added more usage examples

added zeros function, ones function, fixed matrix.empty function performance, optimized matrix constructor to fit ones,zeros and empty matrices construction

added triu function + tests

created tril function, added documentation to most methods, added usage examples

created tri method + tests

created identity function + tests

fixed documentation of empty method

test commit

test push

fixed documentation of empty method

created .empty method. added documentation to some of the functions