Add RTL support to the H5P Editor

[nadavkav]

Link to a remote issue report

[nadavkav]

Feature request for the CKEditor in RTL mode:

• Add CKEditor bidi plugin to the default editor.
• Add detection of user's language, maybe from the HTML parent iframe directionality, to enable relevant LTR/RTL buttons on the CKEditor toolbar and for initially setting config.contentsLangDirection = 'rtl';

[icc]

Will consider this for next release.

[nadavkav]

Sweet