resolves #2, globstars and alike

@jonschlinkert @jonathanong
Guys, cheers! LOL

- Resolves https://github.com/jonschlinkert/strip-comments/issues/2 , globstars and alike.
- added more tests

But something like this one will continue failing. Or at all, is this possible as usecase?
```js
  it('should strip all but not multiple globstars `./path/to/**/*mega/globstar/**/*.txt`', function() {
    var actual = strip("var src = './path/to/**/*mega/globstar/**/*.txt';")
    var expected = "var src = './path/to/**/*mega/globstar/**/*.txt';"
    normalize(actual).should.eql(normalize(expected));
  })
```