* Enforce error handling and checking type assertions
* Reference issue #5404 in the TODO message
* doc description
* Merge branch 'master' into errcheck
* fix tests and address @nisdas feedbacK
* gaz
* fix docker image
* 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
* new interface methods
* support proposer slashings
* add in the new buckets
* all crud for propoer slashings
* attester slashings complete
* all slashings crud done
* right comment
* delete out of scope methods
* conform old beacon DB