* do not use batch for SaveAttestations
* use snappy compression
* Encode / decode everything with snappy
* Add snappy migration path
* batch is probably fine...
* fix test
* gofmt
* Merge branch 'master' of github.com:prysmaticlabs/prysm into remove-batch-attestations
* add sanity check
* remove that thing
* gaz
* Merge branch 'master' of github.com:prysmaticlabs/prysm into remove-batch-attestations
