docs(typescript-config): copy edits applying guidelines (#3383)

Author: kapunahelewong

public/docs/ts/latest/guide/typescript-configuration.jade

@@ -1,29 +1,30 @@
 include ../_util-fns
 
 :marked
-  TypeScript is a primary language for Angular application development. It is a dialect of JavaScript with design-time support for type-safety and tooling.
+  TypeScript is a primary language for Angular application development. 
+  It is a superset of JavaScript with design-time support for type safety and tooling.
 
   Browsers can't execute TypeScript directly. Typescript must be "transpiled" into JavaScript using the *tsc* compiler,
   which requires some configuration.
 
   This page covers some aspects of TypeScript configuration and the TypeScript environment
   that are important to Angular developers, including details about the following files:
 
-  * [tsconfig.json](#tsconfig) - TypeScript compiler configuration.
-  * [typings](#typings) - TypesScript declaration files.
+  * [tsconfig.json](#tsconfig)—TypeScript compiler configuration.
+  * [typings](#typings)—TypesScript declaration files.
 
 a(id="tsconfig")
 .l-main-section
 :marked
   ## *tsconfig.json*
-  Typically, you add a TypeScript configuration file (`tsconfig.json`) to your project to
+  Typically, you add a TypeScript configuration file called `tsconfig.json` to your project to
   guide the compiler as it generates JavaScript files.
 .l-sub-section
   :marked
     For details about `tsconfig.json`, see the official
     [TypeScript wiki](http://www.typescriptlang.org/docs/handbook/tsconfig-json.html).
 :marked
-  We created the following `tsconfig.json` during [Setup](setup.html):
+  The [Setup](setup.html) guide uses the following `tsconfig.json`:
 +makeJson('quickstart/ts/src/tsconfig.1.json', null, 'tsconfig.json')(format=".")
 :marked
   This file contains options and flags that are essential for Angular applications.
@@ -73,39 +74,42 @@ a(id="typings")
   can find them. Angular is one such library. 
   The `node_modules/@angular/core/` folder of any Angular application contains several `d.ts` files that describe parts of Angular.
 
-  **You need do nothing to get *typings* files for library packages that include `d.ts` files—as all Angular packages do.**
+  **You need do nothing to get *typings* files for library packages that include `d.ts` files. 
+  Angular packages include them already.**
 
   ### lib.d.ts
 
   TypeScript includes a special declaration file called `lib.d.ts`. This file contains the ambient declarations for various common JavaScript constructs present in JavaScript runtimes and the DOM.
 
-  Based on the `--target`, TypeScript adds _additional_ ambient declarations like `Promise` if our target is `es6`.
+  Based on the `--target`, TypeScript adds _additional_ ambient declarations 
+  like `Promise` if the target is `es6`.
 
-  Since the QuickStart is targeting `es5`, we can override the list of declaration files to be included:
+  Since the QuickStart is targeting `es5`, you can override the 
+  list of declaration files to be included:
 
 code-example(format=".")
   "lib": ["es2015", "dom"]
 
 :marked
-  Thanks to that, we have all the `es6` typings even when targeting `es5`.
+  Thanks to that, you have all the `es6` typings even when targeting `es5`.
 
   ### Installable typings files
   Many libraries—jQuery, Jasmine, and Lodash among them—do *not* include `d.ts` files in their npm packages.
   Fortunately, either their authors or community contributors have created separate `d.ts` files for these libraries and 
   published them in well-known locations.
 
-  We can install these typings via `npm` using the 
+  You can install these typings via `npm` using the 
   [`@types/*` scoped package](http://www.typescriptlang.org/docs/handbook/declaration-files/consumption.html) 
-  and Typescript (starting at 2.0) will automatically recognize them.
+  and Typescript, starting at 2.0, automatically recognizes them.
 
-  For instance, to install typings for `jasmine` we could do `npm install @types/jasmine --save-dev`.
+  For instance, to install typings for `jasmine` you could do `npm install @types/jasmine --save-dev`.
 
 :marked
-  QuickStart identified two *typings* (`d.ts`) files:
+  QuickStart identifies two *typings*, or `d.ts`, files:
 
-  * [jasmine](http://jasmine.github.io/) typings for the Jasmine test framework
+  * [jasmine](http://jasmine.github.io/) typings for the Jasmine test framework.
 
   * [node](https://www.npmjs.com/package/@types/node) for code that references objects in the *nodejs* environment; 
-  You can view an example in the [webpack](./webpack.html) page.
+  you can view an example in the [webpack](./webpack.html) page.
 
   QuickStart doesn't require these typings but many of the samples do.