storage: Improve coverage of replaced node test without a big slowdown
storage: Improve coverage of replaced node test without a big slowdown

It was so slow because it had to wait at least 9 seconds for the first
range's lease to expire. Backoff delays also added some time on top of
that. Resolve this by cutting down the raft tick interval and election
timeout to speed things up. This has shown to not be flaky.

glycerine/cockroach,maxlang/cockroach,maxlang/cockroach,glycerine/cockroach,maxlang/cockroach,paperstreet/cockroach,glycerine/cockroach,paperstreet/cockroach,glycerine/cockroach,paperstreet/cockroach,petermattis/cockroach,vaibhavarora/cockroach,maxlang/cockroach,vaibhavarora/cockroach,maxlang/cockroach,vaibhavarora/cockroach,petermattis/cockroach,paperstreet/cockroach,petermattis/cockroach,maxlang/cockroach,vaibhavarora/cockroach,petermattis/cockroach,vaibhavarora/cockroach,glycerine/cockroach,glycerine/cockroach,paperstreet/cockroach,vaibhavarora/cockroach,maxlang/cockroach,paperstreet/cockroach,vaibhavarora/cockroach,paperstreet/cockroach,paperstreet/cockroach,petermattis/cockroach,glycerine/cockroach,glycerine/cockroach,petermattis/cockroach,maxlang/cockroach,vaibhavarora/cockroach,petermattis/cockroach,petermattis/cockroach