update CHANGELOG and ignore when checking markdown

Author: matthewhanson

.remarkignore

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+/CHANGELOG.md

CHANGELOG.md

@@ -16,8 +16,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+# [v1.0.0] - 2021-03-08
+
+Initial independent release, see [previous history](https://github.com/radiantearth/stac-spec/commits/v1.0.0-rc.1/extensions/item-assets)
+
+### Fixed
 - Clarified that collection-level asset object properties do  not remove the need for item-level asset object properties
   in the `item-assets` extension ([#880](https://github.com/radiantearth/stac-spec/pull/880))
 - Disallow `href` in JSON Schema
 
-[Unreleased]: <https://github.com/stac-extensions/template/compare/v1.0.0...HEAD>
+[Unreleased]: <https://github.com/stac-extensions/item-assets/compare/v1.0.0...HEAD>
+[v1.0.0]: <https://github.com/stac-extensions/item-assets/tree/v1.0.0>

README.md

@@ -6,7 +6,6 @@
 - **Scope:** Collection
 - **Extension [Maturity Classification](https://github.com/radiantearth/stac-spec/tree/master/extensions/README.md#extension-maturity):** Proposal
 - **Owner**: @matthewhanson
-- **History**: [Prior to March 2, 2021](https://github.com/radiantearth/stac-spec/commits/v1.0.0-rc.1/extensions/item-assets)
 
 This document explains the Item Assets Definition Extension to the 
 [SpatioTemporal Asset Catalog](https://github.com/radiantearth/stac-spec) (STAC) specification.