This commit adds a new option --failures to etcd-tester. The option
receives a comma-delimited argument like this:
"default,failpoints". The given arguments are interpreted as names of
failures and they are injected to an etcd cluster. Available failures
are default (default scenario in etcd-tester) and failpoints. If no
args are passed to the option (--failures=""), no failures are
injected during testing.
7d48855630