* rename state to value in slate core, as deprecation
* rename all references to state to value in slate core
* migrate slate-base64-serializer
* migrate slate-html-serializer
* migrate slate-hyperscript
* migrate slate-plain-serializer
* migrate slate-prop-types
* migrate slate-simulator
* fix change.setState compat
* deprecate references to state in slate-react
* remove all references to state in slate-react
* remove `value` and `schema` from props to all components
* fix default renderPlaceholder
* fix tests
* update examples
* update walkthroughs
* update guides
* update reference
* refactor to extract applyOperation util
* change handlers to receive transform instead of state
* change onChange to receive a transform, update rich-text example
* fix stack iterationg, convert check-list example
* convert code-highlighting, embeds, emojis examples
* change operations to use full paths, not indexes
* switch split and join to be recursive
* fix linter
* fix onChange calls
* make all operations invertable, add src/operations/* logic
* rename "join" to "merge"
* remove .length property of nodes
* fix node.getFragmentAtRange logic
* convert remaining examples, fix existing changes
* fix .apply() calls and tests
* change setSave and setIsNative transforms
* fix insert_text operations to include marks always
* cleanup and fixes
* fix node inheritance
* fix core onCut handler
* skip constructor in node inheritance
* cleanup
* change updateDescendant to updateNode
* add and update docs
* eliminate need for .apply(), change history to mutable
* add missing file
* add deprecation support to Transform objects
* rename "transform" to "change"
* update benchmark
* add deprecation util to logger
* update transform isNative attr
* fix remaining warn use
* simplify history checkpointing logic
* fix tests
* revert history to being immutable
* fix history
* fix normalize
* fix syntax error from merge
