There are (at least) two changes that are breaking:
- defaultTab is gone
- The re-rendering logic looks to have been re-written so that
  passing in a new array of tabs causes a re-render, which can
  reset the currently selected tab.

The fixes involved removing defaultTab from each tab configuration,
as it is no longer respected anyway. Also, instead of letting Tabs
be uncontrolled and allowing it to set its own selected, which
would result in the first tab automatically being selected on
Tabs re-render, use Tabs a controlled prop to dicate which
tab is selected; this is accomplished by specifying a selected
prop.

ESLint 4.8.0 discovers a lot of error related to formatting. While I
tried to fix as many of them as possible, a portion of them actually go
against our coding style. In such a case, I've disabled the indent rule
which effectively leaves it as it was before ESLint 4.8.0.

Additionally, remove jshint because it's becoming a nuisance with its
lack of understanding of ES2015+.

Prepare for React 16.

#1411