chore: update definitions

Update definitions to match those defined by the library author

types/unist/index.d.ts

@@ -1,40 +1,63 @@
 // Type definitions for Unist 2.0
-// Project: https://github.com/syntax-tree/unist
+// Project: https://github.com/syntax-tree/unist-ts
 // Definitions by: bizen241 <https://github.com/bizen241>
 //                 Jun Lu <https://github.com/lujun2>
+//                 Hernan Rajchert <https://github.com/hrajchert>
+//                 Titus Wormer <https://github.com/wooorm>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
-// TypeScript Version: 2.4
+// TypeScript Version: 3.1
 
+export as namespace Unist
+
+// Syntactic units in unist syntax trees are called nodes.
 export interface Node {
+    // The variant of a node.
     type: string;
+
+    // Information from the ecosystem.
     data?: Data;
+
+    // Location of a node in a source document.
+    // Must not be present if a node is generated.
     position?: Position;
 }
 
 export interface Data {
-    [key: string]: any;
+    [key: string]: unknown;
 }
 
+// Location of a node in a source file.
 export interface Position {
+    // Place of the first character of the parsed source region.
     start: Point;
+
+    // Place of the first character after the parsed source region.
     end: Point;
-    /** >= 1 */
-    indent?: number[];
+
+    // Start column at each index (plus start line) in the source region,
+    // for elements that span multiple lines.
+    indent: number[];
 }
 
+// One place in a source file.
 export interface Point {
-    /** >= 1 */
+    // Line in a source file (1-indexed integer).
     line: number;
-    /** >= 1 */
+
+    // Column in a source file (1-indexed integer).
     column: number;
-    /** >= 0 */
+
+    // Character in a source file (0-indexed integer).
     offset?: number;
 }
 
+// Nodes containing other nodes.
 export interface Parent extends Node {
+    // List representing the children of a node.
     children: Node[];
 }
 
+// Nodes containing a value.
 export interface Literal extends Node {
     value: any;
 }

types/unist/unist-tests.ts

@@ -1,5 +1,3 @@
-import * as Unist from 'unist';
-
 const data: Unist.Data = {
     string: 'string',
     number: 1,