* Add double vote detection to spanner
* Add documentation
* Update slasher/detection/attestations/spanner.go
* Merge branch 'master' of https://github.com/prysmaticlabs/Prysm into slasher-spanner-double
* Merge branch 'slasher-spanner-double' of https://github.com/0xKiwi/Prysm into slasher-spanner-double
* Merge branch 'master' of https://github.com/prysmaticlabs/Prysm into slasher-spanner-double
* Gazelle
* Add double vote detection func
* Implement double voting detection
* Merge branch 'master' of https://github.com/prysmaticlabs/Prysm into slasher-implement-double
* Merge branch 'master' into slasher-implement-double
* Merge branch 'slasher-implement-double' of https://github.com/0xKiwi/Prysm into slasher-implement-double
* Fix typo
* Remove filter, replace with slot + committee index
* Change bloom filter to 2 sig bytes
* Merge branch 'master' of https://github.com/prysmaticlabs/Prysm into slasher-change-filter
* Merge branch 'master' of https://github.com/prysmaticlabs/Prysm into slasher-implement-double
* Merge branch 'slasher-change-filter' of https://github.com/0xKiwi/Prysm into slasher-implement-double
* Change detection to use prefix
* Fix runtime
* Merge branch 'master' of https://github.com/prysmaticlabs/Prysm into slasher-implement-double
* Fix bug and comments
* Merge branch 'master' of https://github.com/prysmaticlabs/Prysm into slasher-implement-double
* Fix flaky test
* Merge branch 'master' into slasher-implement-double
* Improve logs
* Merge branch 'slasher-implement-double' of https://github.com/0xKiwi/Prysm into slasher-implement-double
* Add ok check
* Fix test
* Merge branch 'master' into slasher-implement-double
* Add simple bloom filter implementation for detecting similarity of 1 key
* Change hash to keccak
* Fix receiver name
* Fix bug
* Fix comments and organize test
* Add comment detailing hash functions
* Add bloom to test names
* Rename vars for clarity
* Change spanner to take target epoch as key
* Fix tests, add multiple val test
* Fixes
* Change the spanner to take in att on detect
* Add back proto diagram tests
* Remove unneeded comments
* more spanner additions
* implement iface
* begin implement
* wrapped up spanner functions
* rem interface
* added in necessary comments
* comments on enums
* begin adding tests
* test for detection
* add all detection tests
* moar tests
* tests for deleting pass
* dd test for update spans
* tests for updating
* include tracing utils
* gaz
* add mutexes
* ivan feedback
* visibility added
* register in node
* fixed up imports
* include detection listeners for feed
* subscribe to blocks and todos
* tests passing
* todos
* pkg comment