api: implement clear snapshot
api: implement clear snapshot

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

avikivity/scylla,duarten/scylla,avikivity/scylla,kjniemi/scylla,raphaelsc/scylla,kjniemi/scylla,raphaelsc/scylla,kjniemi/scylla,raphaelsc/scylla,scylladb/scylla,scylladb/scylla,duarten/scylla,duarten/scylla,scylladb/scylla,avikivity/scylla,scylladb/scylla