doc: release notes for html/template
doc: release notes for html/template

Change-Id: Ifdc3c5b840e6833f14c8e52948e45d5faa5a0615
Reviewed-on: https://go-review.googlesource.com/c/go/+/181940
Reviewed-by: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>

nawawi/go,cloudflare/go,CAFxX/go,golang/go,nawawi/go,golang/go,nawawi/go,CAFxX/go,cloudflare/go,akutz/go,nawawi/go,CAFxX/go,akutz/go,golang/go,cloudflare/go,golang/go,nawawi/go,cloudflare/go,golang/go,nawawi/go,akutz/go,CAFxX/go,cloudflare/go,CAFxX/go,akutz/go,cloudflare/go,CAFxX/go,nawawi/go,akutz/go,nawawi/go,golang/go,akutz/go,akutz/go,cloudflare/go,CAFxX/go,golang/go,cloudflare/go,CAFxX/go,golang/go,akutz/go