RFR: Section on project maintenance [v4]

[Jesper Wilhelmsson]

On Thu, 6 Oct 2022 19:09:04 GMT, Jesper Wilhelmsson <jwilhelm at openjdk.org> wrote:

>> * New section on project maintenance
>> * New infographics on push/defer during rampdown
>> * Moved JDK Release Process section to follow the Release Note section
>> * Minor fixes
>
> Jesper Wilhelmsson has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Additions from Simms

Thank you all for your reviews! I believe all comments have been incorporated into the text now.

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PR: https://git.openjdk.org/guide/pull/92