sf build -tags sqliteanalysis

// PREPARATORY CHANGES TO SF 
1. Use existing -hash flag but change behaviour so can accept a comma separated list of hashes e.g. -hash md5,ssdeep
2. change hash.go file (under /cmd/) so that checksum var is a slice of hashes var checksum []hash.Hash
3. writer interface (cmd/writers.go) updated so writeFile method takes a slice of byte slices for checksum digests (checksum [][]byte)
And all writers (JSON, CSV, YAML etc) updated so they can accept multiple checksum digests.
4. in cmd/sf.go update the identifyRdr func so it ranges through the slice of checksums, calculating for each, and returns a slice of byte slices for checksum digests

// SQLITEANALYSIS CHANGES
5. copy the hash.go flag as hash_sqliteanalysis.go and prepend build tag
6. add spamspam as an import and update the functions in this file
May need to add a SpamHash type that wraps SpamSpamWriter // type SpamHash struct {SpamSpamWriter}.
This will allow overriding the Sum method so that it returns content of the SpamSpamWriter String() method as a byte slice, rather than existing Sum method which doesn't seem to give expected result.