[DOCS] Fix link to statsd plugin

Fixes #4128
Just filter test jar and not the main jar file
s/AbstractIntegrationTest/ElasticsearchIntegrationTest
Squashed old stuff :D
CircuitBreaker as part of builder, transition circuit breaker to per-node service
remove unused breaker
refactor old code, remove unused stuff
remove InternalEstimateFacet
misc cleanup
Still has kinks, but working service
change CircuitBreaker into interface
a bit of refactoring just moving around
Use real values for used when refreshing
documentation, refactoring and licenses
reset cluster name
add license header
Rename CircuitBreaker -> MemoryCircuitBreaker
add contstant factor, add documentation
add constant overhead to dynamic settings
remove unneeded things