chapters/appendix-VI: Drop the weakly-referenced external identifiers

And renumber the old CC BY 3.0 from VII to VI.

SUMMARY.md

@@ -15,5 +15,4 @@
 * [Appendix III: RDF Data Model Implementation and Identifier Syntax](./chapters/appendix-III-RDF-data-model-implementation-and-identifier-syntax.md)
 * [Appendix IV: SPDX License Expressions](./chapters/appendix-IV-SPDX-license-expressions.md)
 * [Appendix V: Using SPDX short identifiers in Source Files](./chapters/appendix-V-using-SPDX-short-identifiers-in-source-files.md)
-* [Appendix VI: External Repository Identifiers](./chapters/appendix-VI-external-repository-identifiers.md)
-* [Appendix VII: Creative Commons Attribution License 3.0 Unported](./chapters/appendix-VII-creative-commons-attribution-license-3.0-unported.md)
+* [Appendix VI: Creative Commons Attribution License 3.0 Unported](./chapters/appendix-VI-creative-commons-attribution-license-3.0-unported.md)

chapters/1-rationale.md

@@ -82,10 +82,12 @@ Companies and organizations (collectively “Organizations”) are widely using
 
 **1.8.2** External Packages can now be refered to in SPDX documents. When there is no SPDX file information available to document the content of these external packages, then the filesAnnalyzed attribute on a package should be set to false. See [section 3.8](3-package-information.md#3.8) Files Analyzed for more information.
 
-**1.8.3** Packages are now able to associate with an “External Reference” which allows a Package to reference an external source of additional information, metadata, enumerations, asset identifiers, or downloadable content believed to be relevant to the Package. See: section [3.21 External Reference](3-package-information.md#3.21), [3.22 External Reference Comment](3-package-information.md#3.22) and [Appendix VI: External Repository Identifiers](./appendix-VI-external-repository-identifiers.md) for more information.
+**1.8.3** Packages are now able to associate with an “External Reference” which allows a Package to reference an external source of additional information, metadata, enumerations, asset identifiers, or downloadable content believed to be relevant to the Package.
+See section [3.21 External Reference](3-package-information.md#3.21) and [3.22 External Reference Comment](3-package-information.md#3.22).
+There used to be an appendix about External Repository Identifiers, but that was never clearly referenced, and the appendix was dropped in version 2.2.
 
 **1.8.4** The “Artifact of Project” fields at the file level are now deprecated, as they can be replaced by a relationship to the more descriptive External Packages.
 
 **1.8.5** A new appendix “Using SPDX short identifiers in Source Files” has been added to document the best practices to refer to the licenses in the SPDX license list that have emerged from the development community. See [Appendix V: Using SPDX short identifiers in Source Files](./appendix-V-using-SPDX-short-identifiers-in-source-files.md) for more information.
 
-**1.8.6** Miscellaneous bug fixes as reported on the mailing list and reported in bugs.linuxfoundation.org (search for SPDX specification).
+**1.8.6** Miscellaneous bug fixes as reported on the mailing list and reported in bugs.linuxfoundation.org (search for SPDX specification).

chapters/appendix-VII-creative-commons-attribution-license-3.0-unported.md → chapters/appendix-VI-creative-commons-attribution-license-3.0-unported.md

@@ -1,4 +1,4 @@
-# Appendix VII: Creative Commons Attribution License 3.0 Unported
+# Appendix VI: Creative Commons Attribution License 3.0 Unported
 
 **License**