Document transcripts.

[rosiel]

Purpose / why

Document how transcripts work in Islandora.

What changes were made?

A page was added outlining how transcripts can be used.

Verification

The claims made can be validated with an installation of islandora defaults

Interested Parties

@Islandora/documentation

Checklist

Pull-request Reviewer

Pull-request reviewer should ensure the following:

• Does this PR link to related issues?
• Does the proposed documentation align with the Islandora Documentation Style Guide?
• Are the changes accurate, useful, free of typos, etc?

Person Merging

The person merging should ensure the following:

• Does mkdocs still build successfully? (This is indicated by TravisCI passing. To test locally, and see warnings, see How To Build Documentation.)
• If pages are renamed or removed, have all internal links to those pages been fixed?
• If pages are added, have they been linked to or placed in the menu?
• Did the PR receive at least one approval from a committer, and all issues raised have been addressed?

[inikolaidis]

I attempted to follow these instructions in the sandbox, not realising defaults is not a part of sandbox. An installation with Islandora Defaults is required to go through transcripts steps

[rosiel]

Thanks for testing! Yes, that is... An issue.

Transcripts should be testable in the sandbox if you add a "media track" type field in the Audio or Video media types.

To be pedantic, Defaults is part of the Sandbox, it's just that the Install Profile clobbers over all Defaults configs with their own. Also as we are getting rid of Defaults soon, it's worth mentioning that transcripts behaviour is part of its successor, the Starter site.

[rosiel]

i'll fix the merge conflict.