Add basic support for EPUB 2.0.1

[rdeltour]

Support EPUB 2.0.1 should not be terribly costly. It requires:

• minor tweaks to the OPF parsing logic
• adding a way to retrieve the NCX and convert it to an outline

[TamJ]

Hi!
I have tested the kb.daisy recommendations for adding accessibility metadata for epub 2.0.1. But ACE 1.1.1 doesn't seem to recognize this syntax. Is that intended to be a part of the support this issue addresses?
/Tam

[marisademeglio]

Here's a user report regarding this same issue with EPUB2 metadata: https://twitter.com/isadoracal/status/1300903307611955203

[danielweck]

Hello Marisa, I suspect the problem occurs with Ace 1.1.1, but not with the latest Ace App (which under the hood uses the latest Ace “core” 1.2)

https://github.com/daisy/ace-gui/releases/tag/v1.1.2

https://www.npmjs.com/package/@daisy/ace/v/1.2.0-beta.12

Is there an EPUB file we could try to reproduce the bug with?

[marisademeglio]

I see, so the ace-next branch with this code is used in Ace app 1.1.2 ?

[marisademeglio]

I tested with an EPUB from the user, and I can confirm that Ace App 1.1.2 does not have this issue and appears to support EPUB2 package metadata.

[TamJ]

Many thanks! I see also that support exists for EPUB2 package metadata. Currently using v 1.2.6.