KAFKA-16429: Enhance all configs which can trigger rolling of new segment

[brandboat]

related to https://issues.apache.org/jira/browse/KAFKA-16429.

Update the document about broker/topic side retention and segment configurations.

Committer Checklist (excluded from commit message)

• Verify design and implementation
• Verify test coverage and CI build status
• Verify documentation (including upgrade notes)

[brandboat]

Apologies for the late pr, gentle ping @showuon , @chia7712 , @jeqo . Could you take a look when you are available ? Many thanks 😃

[showuon]

@brandboat , thanks for the PR. But sorry, I think we seem to make the document more unreadable after this change. For example, as a first kafka user, when reading segment.bytes config description, it's confusing what it means this config

"operates independently of \"retention.ms\",\"retention.bytes\", \"log.retention.ms\", \"log.retention.minutes\", ...

I'm thinking we could add a more section here to talk about when log segment will be rolled. I'm expecting we should say something about when the log segment will be rolled, when:

1. segment roll time expired: segment.ms, log.roll.hours, ...
2. segment roll size exceeded: segment.bytes, log.segment.bytes, ...
3. retention time expired: retention.ms, ...
4. retention size is 0: retention.bytes
   And then we can give some examples in the section. WDYT?

I had a quick read for the write section, I found it is not completely correct, and unreadable.

1. This file is rolled over to a fresh file when it reaches a configurable size (say 1GB).
   -> this is not completely correct because segment.ms expiration will also roll the segment.
2. The log takes two configuration parameters: M, .... and S, ....
   -> What is the magic parameter M and S???????
   We should update them as flush.messages and flush.ms

This can be opened as a separate PR.