* Add flag for attester protection
* Remove flags
* Add attestation history DB functions to validator client
* Fix comments
* Update interface to new funcs
* Fix test
* Add flags
* Implement most of attester protection
* Fix tests
* Add test for pruning
* Add more test cases for prunes
* Remove todo comment
* Fix comments
* Rename functions
* Fix logs
Co-authored-by: Raul Jordan <raul@prysmaticlabs.com>