v1.0.0-alpha.1

Bug fixes

• ContextualBalloon should remember position passed to #updatePosition(). Closes #305. Closes ckeditor/ckeditor5-image#141. (c787c0d)
• ContextualToolbar should not be positioned to a zero–width DOM rect when invoked for a multi-line forward selection. Closes #308. (00b701b)
• ContextualToolbar will accept the object format of config.contextualToolbar. Closes #316. (d71cad8)
• Fixed sticky panel's z-index so it's correctly rendered above images (or other relatively positioned elements). Closes #315. (00f2add)
• The content of the BalloonPanelView should be selectable. Closes #294. Closes ckeditor/ckeditor5#498. (e5315df)

Features

• Implemented View#removeChildren(), the opposite of View#addChildren(). Closes #303. (0f1ea5a)
• Replaced StickyToolbarView with a generic StickyPanelView. Closes #297. (b10b43c)

Other changes

• ToolbarView#fillFromConfig() will warn when the factory does not provide a component. Closes #291. Closes ckeditor/ckeditor5#526. (2e63e70)
• The escPressHandler function should be replaced by the KeystrokeHandler. Closes #150. (b322744)

BREAKING CHANGES

• Toolbar#fillFromConfig() cannot be now called with an undefined. Make sure to use normalizeToolbarConfig() to get a reliable object.
• The escPressHandler is no longer available. Please
  refer to the KeystrokeHandler helper to learn more.
• The StickyToolbarView and corresponding CSS .ck-sticky-panel classes are no longer available. StickyPanelView + ToolbarView combo should be used instead.