Update CoffeeScript from v1.6.2 to v1.7.1

Simply updated `coffee-script.js` from version `1.6.2` to `1.7.1`
While many changes were specific to `node` et al, there were some important changes to the language proper. The list below is from the official [changelog][1]. Also, here is the full list of [commits][2] for your perusal. Hope all is well.

**1.7.1 – JANUARY 29, 2014**
- Fixed a typo that broke node module lookup when running a script directly with the `coffee` binary.

**1.7.0 – JANUARY 28, 2014**
- When requiring CoffeeScript files in Node you must now explicitly register the compiler. This can be done with `require 'coffee-script/register'` or `CoffeeScript.register()`. Also for configuration such as Mocha's, use **coffee-script/register**.
- Improved error messages, source maps and stack traces. Source maps now use the updated `//#` syntax.
- Leading `.` now closes all open calls, allowing for simpler chaining syntax.
```coffee
$ 'body'
.click (e) ->
  $ '.box'
  .fadeIn 'fast'
  .addClass '.active'
.css 'background', 'white'
```
```javascript
$('body').click(function(e) {
  return $('.box').fadeIn('fast').addClass('.active');
}).css('background', 'white');
```
- Added `**`, `//` and `%%` operators and `...` expansion in parameter lists and destructuring expressions.
- Multiline strings are now joined by a single space and ignore all indentation. A backslash at the end of a line can denote the amount of whitespace between lines, in both strings and heredocs. Backslashes correctly escape whitespace in block regexes.
- Closing brackets can now be indented and therefore no longer cause unexpected error.
- Several breaking compilation fixes. Non-callable literals (strings, numbers etc.) don't compile in a call now and multiple postfix conditionals compile properly. Postfix conditionals and loops always bind object literals. Conditional assignment compiles properly in subexpressions. `super` is disallowed outside of methods and works correctly inside `for` loops.
- Formatting of compiled block comments has been improved.
- No more `p` folders on Windows.
- The `options` object passed to CoffeeScript is no longer mutated.

**1.6.3 – JUNE 2, 2013**
- The CoffeeScript REPL now remembers your history between sessions. Just like a proper REPL should.
- You can now use `require` in Node to load `.coffee.md` Literate CoffeeScript files. In the browser, `text/literate-coffeescript` script tags.
- The old `coffee --lint` command has been removed. It was useful while originally working on the compiler, but has been surpassed by JSHint. You may now use `-l` to pass literate files in over stdio.
- Bugfixes for Windows path separators, `catch` without naming the error, and executable-class-bodies-with- prototypal-property-attachment.

[1]: http://coffeescript.org/#changelog
[2]: https://github.com/jashkenas/coffee-script/compare/1.6.2...1.7.1