sstables: Import EstimatedHistogram.java
sstables: Import EstimatedHistogram.java

Signed-off-by: Raphael S. Carvalho <1e2942cea40e3b4d2162dfcd9e53e41c05a84d22@cloudius-systems.com>

capturePointer/scylla,phonkee/scylla,rluta/scylla,capturePointer/scylla,eklitzke/scylla,acbellini/scylla,guiquanz/scylla,avikivity/scylla,eklitzke/scylla,dwdm/scylla,kangkot/scylla,acbellini/scylla,dwdm/scylla,duarten/scylla,avikivity/scylla,victorbriz/scylla,justintung/scylla,senseb/scylla,aruanruan/scylla,acbellini/scylla,wildinto/scylla,victorbriz/scylla,duarten/scylla,rentongzhang/scylla,bowlofstew/scylla,wildinto/scylla,senseb/scylla,aruanruan/scylla,capturePointer/scylla,scylladb/scylla,bowlofstew/scylla,raphaelsc/scylla,asias/scylla,raphaelsc/scylla,rluta/scylla,rentongzhang/scylla,kjniemi/scylla,linearregression/scylla,wildinto/scylla,guiquanz/scylla,tempbottle/scylla,linearregression/scylla,justintung/scylla,shaunstanislaus/scylla,linearregression/scylla,gwicke/scylla,rentongzhang/scylla,glommer/scylla,rluta/scylla,respu/scylla,scylladb/scylla,stamhe/scylla,bowlofstew/scylla,raphaelsc/scylla,dwdm/scylla,justintung/scylla,respu/scylla,phonkee/scylla,scylladb/scylla,kjniemi/scylla,gwicke/scylla,glommer/scylla,tempbottle/scylla,victorbriz/scylla,asias/scylla,eklitzke/scylla,stamhe/scylla,phonkee/scylla,tempbottle/scylla,shaunstanislaus/scylla,guiquanz/scylla,aruanruan/scylla,asias/scylla,shaunstanislaus/scylla,kangkot/scylla,scylladb/scylla,kangkot/scylla,respu/scylla,senseb/scylla,duarten/scylla,stamhe/scylla,kjniemi/scylla,gwicke/scylla,avikivity/scylla,glommer/scylla