Add more hash for content comparisons: CRC32 sha1 sha256

[beng-tang]

Hi just a suggestion to add options to use different checksum methods to check file contents:
CRC32, sha1, and sha256, in addition to MD5.

[arsenetar]

We no longer use md5, and use xxhash for file hashing (there is fallback to md5 but all official builds will end up using xxhash). I don't see a strong reason to support multiple hashing algorithms as it adds complexity without really bringing much benefit.