Rename "state" to "value" everywhere (#1313)

* 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

packages/slate-hyperscript/src/index.js

@@ -1,6 +1,7 @@
 
 import isEmpty from 'is-empty'
 import isPlainObject from 'is-plain-object'
+import logger from 'slate-dev-logger'
 
 import {
   Block,
@@ -9,8 +10,8 @@ import {
   Mark,
   Node,
   Range,
-  State,
-  Text
+  Text,
+  Value,
 } from 'slate'
 
 /**
@@ -74,7 +75,12 @@ const CREATORS = {
     return Range.create(attributes)
   },
 
-  state(tagName, attributes, children) {
+  state(...args) {
+    logger.deprecate('slate-hyperscript@0.3.0', 'The `<state>` tag has been renamed to `<value>`.')
+    return CREATORS.value(...args)
+  },
+
+  value(tagName, attributes, children) {
     const { data } = attributes
     const document = children.find(Document.isDocument)
     let selection = children.find(Range.isRange) || Range.create()
@@ -110,8 +116,8 @@ const CREATORS = {
       selection = selection.merge(props).normalize(document)
     }
 
-    const state = State.create({ data, document, selection })
-    return state
+    const value = Value.create({ data, document, selection })
+    return value
   },
 
   text(tagName, attributes, children) {