General cleanup and add option to disable compression
This MR does two things:
- General cleanup
- Remove copy-pasted libs3 sources and use CMake FetchContent
- Add rpm packaging - modify binary name so it is less generic when installed
- Fix bucket naming - we were using invalid '_' characters in bucket names both in the code and sample config, switch to '-'.
- Add docs on building lustre and testing with s3
- Clarify build requirements in docs
- Fix some minor warnings - don't inline ct_now() and include suitable system time header
- Optional to disable compression In the config file if 'use_compression' is false-like we will no longer use lz4 and advertise content as octet stream.