Fixing broken mobile navbar.

By adding in the required Javascript:

- bootstrap
- jquery

And modifying the navbar HTML elements slightly (convert the div to a nav
element, move the navbar inside of the container), I was able to get the menu
clickable.

There is still work to be done for styling -- the menu items are transparent, so
it looks bad.
Fixing style of collapsable navbar, simplifying code slightly.
Whitespace.
Adjusting columns depending on screen size for main docs.
Replacing old styles with new ones to simplify sidebar design.
Fixing intro wording -- sounded weird.
Updating intro wording to be a bit more clear.
Whitespace.
Updating links in quickstart intro, also shortening file path for properties
file.

(tilda convention)
Changing comments in code to be a bit more friendly ^^
Whitespace.
Adding colon for consistency.
Cleaning up formatting of code sample slightly.
Simplifying example again.
Updating code sample for application / directory listings.

Made it work with the new SDK stuff.
Adding a note about the expansion.
Making the menu display on tablets too.
Updating section title for consistency.
Updating code / docs for 'Retrieve a Specific Resource' section.
Updating the docs / code samples for 'Create Application' docs.