docs: add Palm.4 to list of releases

[cmltaWt0]

Adds the new Palm.4 release that was tagged 16/11 to the list of releases.

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[cmltaWt0]

@mariajgrimaldi @kdmccormick Please review this (a bit delayed).

[cmltaWt0]

@pdpinch Notifying you that I want to merge this.

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