Thorium ports

[JayPanoz]

Please check if the PR fulfills these requirements:

(Add x between brackets to check.)

• I’ve read contributing guidelines
• I’m making this pull request against the develop branch
• I’ve updated from the develop branch before proposing this pull request
• I’ve tested the changes for bug fixes and/or features
• I’ve documented new code

What kind of change does this PR introduce? (Bug fix, feature, docs update, other)

This PR implement Thorium changes that can be useful to all consumers of ReadiumCSS.

Specifically:

• it resolves Letter-spacing for japanese #136
• it resolves User setting to disable/hide ruby #140
• it fixes Width and height safeguards hide audio controls + video #94
• it fixes forcing "start" text alignment (left or right depending on document language) does not work with "inherit" #128

Does this PR introduce a breaking change? (What changes might users need to make in their application due to this PR?)

It should only introduce fixes and new user settings. That said the situation may be slightly different for Thorium and other apps having handled #94 and #128, given the fixes and features are already implemented in another way.

Otherwise, it’s 2 extra user settings to implement:

• letter-spacing in CJK
• hiding ruby annotation using a new flag --USER__no-ruby: readium-noRuby-on (part of settings requiring the advanced flag).

Other information:

I guess @danielweck would be the best one to check/review this PR, considering his changes are ported into ReadiumCSS as a whole.

But any feedback welcome, especially on hiding ruby annotation cos’ naming things is hard, and perhaps we don’t want to tie it to advanced settings, it should just be its own thing with no other flag required.

[JayPanoz]

@danielweck does this look good to you?

As a reminder, this will be tagged as the last of version 1 in the main branch in order to push version 2 on develop.

[JayPanoz]

Note: In order to progress on v2, and make it available for testing ASAP, it’s been discussed we pull these changes into develop and postpone the review to develop → master.

As a reminder, once pulled in master, this will be tagged as the last version 1. Work on version 2 will then be carried into develop.