Stack overflow on Windows

[maxosprojects]

Platform: Windows 10
Atom: 1.29.0 x64
atom-mocha-test-runner: 1.0.0

Reproduce
Run tests with Ctrl-Alt-M

Expected
Tests run and results are displayed

Observed
Error pane shows up with the following error:

Uncaught RangeError: Maximum call stack size exceeded
    at normalizeStringWin32 (path.js:33:30)
    at Object.normalize (path.js:440:14)
    at Object.join (path.js:562:18)
    at closestPackage (file:///C:/Users/User/.atom/packages/mocha-test-runner/lib/context.coffee:25:14)
    at closestPackage (file:///C:/Users/User/.atom/packages/mocha-test-runner/lib/context.coffee:31:5)
    at closestPackage (file:///C:/Users/User/.atom/packages/mocha-test-runner/lib/context.coffee:31:5)
    at closestPackage (file:///C:/Users/User/.atom/packages/mocha-test-runner/lib/context.coffee:31:5)
    at closestPackage (file:///C:/Users/User/.atom/packages/mocha-test-runner/lib/context.coffee:31:5)
    .
    .
    .

Notes:
Apparently root check in closestPackage isn't supposed to work on Windows.

closestPackage = (folder) ->
  pkg = path.join folder, 'package.json'
  if fs.existsSync pkg
    folder
  else if folder is '/'
    null
  else
    closestPackage path.dirname(folder)

Suggested fix:

closestPackage = (folder) ->
  pkg = path.join folder, 'package.json'
  if fs.existsSync pkg
    folder
  else if folder is path.parse(folder).root
    null
  else
    closestPackage path.dirname(folder)

Will, probably, do a PR later.