HTML5 Boilerplate links changed

[gnanet]

In section Other Resources both urls lead to a 404, seems the structure of h5bp repository changed, documentation folder was moved to its own location:

In the 2 urls its a simple replace from dist/doc to docs. I would say, this change does not need a full blown PR.

The fixed lines would be:

- 📖 [HTML5 Boilerplate Docs: The HTML](https://github.com/h5bp/html5-boilerplate/blob/master/docs/html.md)
- 📖 [HTML5 Boilerplate Docs: Extend and customize](https://github.com/h5bp/html5-boilerplate/blob/master/docs/extend.md)

[AnuragNishad12]

I fix this issue needed approval Here's the link Of My Commit https://github.com/joshbuchea/HEAD/pull/285/commits/e83c991d8411922c8cb3f88e01db1dd75443732a