evaluate and add in ulimits, process limits, sysctl reqs, etc.

[aegershman]

As according to yugabyte doc under 'manual deployment', and with bpm. see this comment in this PR for more details about limits and bpm

also, the security-checklist may have helpful info https://docs.yugabyte.com/latest/secure/security-checklist/

see:

• https://ro-che.info/articles/2017-03-26-increase-open-files-limit
• https://gemfire.docs.pivotal.io/99/geode/managing/heap_use/lock_memory.html
• usage of file-nr?
• need to bump the timeout on monit way up? https://starkandwayne.com/blog/quick-guide-to-using-monit-in-bosh/
• https://github.com/pivotal-cf/ulimit-release/blob/master/jobs/ulimit/spec maybe it needs to be specified in /etc/limits.conf
• https://github.com/cloudfoundry-incubator/docker-boshrelease/issues/37
• https://github.com/maartensl/cf-release-ulimits/commit/f78dae0dd3f9a14381fd7727e83d35be40c9089d
• some interesting things that bosh cassandra release does: https://github.com/orange-cloudfoundry/cassandra-boshrelease/blob/master/jobs/cassandra/templates/bpm-prestart
• and pxc-release does: https://github.com/cloudfoundry-incubator/pxc-release/blob/master/jobs/pxc-mysql/spec
• good inspiration: https://github.com/cloudfoundry/nats-release/blob/develop/jobs/nats/templates/pre-start.erb

[aegershman]

I think it's safe to say this is good enough to be closed