Document that reflections on Low graphics preset is disabled by design

[canny]

Under the current release 7.1.11.12363455226 it appears under the low preset reflections are all disabled. Looking over the release notes I only see mention of the HDR and Emissive option under advanced which switching this on and off makes no difference.

See attached images and also note that even on low preset probes no longer function as I can set them to even full scene but they do not display.

https://secondlife.canny.io/admin/board/bug-reports/p/extrafps-7111-missing-reflections-on-preset

[canny]

This issue has been linked to a Canny post: ExtraFPS 7.1.11 missing reflections on preset 🎉

[Dan-Linden]

When Graphics Quality is set to Low, RenderReflectionsEnabled is set to 0, which disabled Reflection probes.

When Reflection probes are disabled, the UI for reflections should be disabled in Advanced Graphics Preferences.

We should make a blog documenting what Low mode does.

[kylelinden]

We need to document the new expectations for "Low" settings which is essentially now a "vintage" support mode.