add insertText command

packages/tiptap-commands/src/commands/insertText.js

@@ -0,0 +1,10 @@
+export default function (text = '') {
+	return (state, dispatch) => {
+		const { $from } = state.selection
+		const { pos } = $from.pos
+
+		dispatch(state.tr.insertText(text, pos))
+
+		return true
+	}
+}