(large update)

[bugfix] incorrect build.py clause

Former-commit-id: 7ce7b3c

Revise lossless compression options in README

Former-commit-id: 68c47c5

Merge pull request szcompressor#32 from wenyugai/feature/nvcomp

add googletest framework to enable CI test

Former-commit-id: d1ad703

fix tar path issue

Former-commit-id: 440ba6b

add script info to README

Former-commit-id: 750f29d

update sample perf.; fix format

Former-commit-id: 658cea7