Fixed broken links (gatsbyjs#880)

docs/blog/gatsbygram-case-study/index.md

@@ -245,7 +245,7 @@ As you can see above, when defining a page, we can set "context" data, which is
 passed as a `prop` to the component and as a [GraphQL
 variable](http://graphql.org/learn/queries/#variables) in our `GraphQL` query.
 For the "[post
-template](https://github.com/gatsbyjs/gatsby/blob/1.0/examples/gatsbygram/templates/template-post-page.js)",
+template](https://github.com/gatsbyjs/gatsby/blob/1.0/examples/gatsbygram/src/templates/post-page.js)",
 we pass the id to the post. Below we use that id to query our `GraphQL` schema
 and return a fully formed page:
 
@@ -328,9 +328,9 @@ Gatsbygram's `about.js` is a simple React component with no query.
 has an infinite scroll implementation to lazy load in image thumbnails.
 
 [Read pages/index.js on
-Github](https://github.com/gatsbyjs/gatsby/blob/1.0/examples/gatsbygram/pages/index.js)  
+Github](https://github.com/gatsbyjs/gatsby/blob/1.0/examples/gatsbygram/src/pages/index.js)  
 [Read pages/about.js on
-Github](https://github.com/gatsbyjs/gatsby/blob/1.0/examples/gatsbygram/pages/about.js)
+Github](https://github.com/gatsbyjs/gatsby/blob/1.0/examples/gatsbygram/src/pages/about.js)
 
 ## The Layout Component
 
@@ -379,7 +379,7 @@ sites as it has logic to show clicked images in either a modal on larger
 screens or on their own page on smaller screens.
 
 [Read Gatsbygram's Layout component on
-Github](https://github.com/gatsbyjs/gatsby/blob/1.0/examples/gatsbygram/layouts/default.js).
+Github](https://github.com/gatsbyjs/gatsby/blob/1.0/examples/gatsbygram/src/layouts/default.js).
 
 ## Client routing and pre-caching