Switch store to etcd

[Frostman]

• Remove bolt from tools/stress.sh
• Update docs/architecture.md with etcd
• Add etcd to instructions on how to run aptomi
• Update install script
• Consider updating docs/asciinema/install.json
• Drop bolt from dependencies (glide)
• Add tls and auth config for etcd
• Make with_etcd.sh run with tls/auth to test prod case
• Create store testing tool and run tests for all stores and codecs
• Consider running compactor for etcd
• Keep only gob and check if we need to pass info.New() into codec in that case
• Update helm chart
• Ensure that by default tests will not run etcd tests?
• Ensure near to 100% non-error code coverage in store package
• Resolve todos in store/etcd impl
• More checks and better errors in store/etcd impl