database: generate UUIDs compatible with Cassandra 2.1.8
database: generate UUIDs compatible with Cassandra 2.1.8

Without this, Cassandra won't even try to read our sstables. The containing
directories will be ignored.

Signed-off-by: Glauber Costa <f8b79557d19b40666ebe336545a0b6178af65685@cloudius-systems.com>

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