Rename editor#dataReady event as editor.data#ready

[f1ames]

Suggested merge commit message (convention)

Other: Introduced editor.data#ready event.

BREAKING CHANGE: The editor#dataReady event was removed. The editor.data#ready event has been introduced and should be used instead.

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Additional information

See ckeditor/ckeditor5#1477 for more details. This PR mostly covers renaming dataReady event (but also necessary adjustments to new plugins#ready event). The second PR (renaming pluginsReady event) is ckeditor/ckeditor5-core#157.

Created ckeditor5 branch with all the changes - https://github.com/ckeditor/ckeditor5/tree/t/1477.

The list of related PRs in other repos which needed adjustments:

• ckeditor5-autosave - Adjustments to new data#ready event ckeditor5-autosave#22
• ckeditor5-core - Rename editor#pluginsReady event as editor.plugins#ready ckeditor5-core#157
• ckeditor5-editor-balloon - Adjustments to new data#ready event ckeditor5-editor-balloon#27
• ckeditor5-editor-classic - Adjustments to new data#ready event ckeditor5-editor-classic#80
• ckeditor5-editor-decoupled - Adjustments to new data#ready event ckeditor5-editor-decoupled#26
• ckeditor5-editor-inline - Adjustments to new data#ready event ckeditor5-editor-inline#46
• ckeditor5-ui - Adjustments to new data#ready event ckeditor5-ui#464
• ckeditor5-paragraph - Adjustments to new data#ready event ckeditor5-paragraph#40

[coveralls]

Coverage remained the same at 100.0% when pulling 039af53 on t/ckeditor5/1477 into df8a777 on master.