1. fix typo: `atleast` -> `at least`
2. add missing `--` from `--bootstrap-servers` argument to be consistent
3. rephrase a sentence, to make it more clear:
before: `LinkedIn is currently running JDK 1.8 u5 (looking to upgrade to a newer version) with the G1 collector`
It will misguide the users to use JDK 1.8 u5, while the JDK 1.8 u251 is already released, which will include many important bug fixes. I did some rephrase as below:
after: `At the time this is written, LinkedIn is running JDK 1.8 u5 (looking to upgrade to a newer version) with the G1 collector`
Reviewers: Konstantine Karantasis <konstantine@confluent.io>