Update 3.4 release candidate notes using generated release_noter parts
Update 3.4 release candidate notes using generated release_noter parts

Standardize the whole page template using release_noter's new template.
The latter is partially based on practices from previous release notes,
with improvements starting here.

Change-Id: If51978c3016893e5a0b1d43f9dfefb46d7361dc0

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