Resolve issue #663 and add test.

* Fixes CLI tests for windows

* Hijacked exec so we don't have to wrap each command in changeForOS, and made replacing 'cat' safer with word boundaries

* Fixing changed tests to be more consistent with the code base

It was not being asserted anywhere else, and I was suspecting that
PR #552 was changing current (and correct) behaviour.

Either vim or git was going crazy with the indentation when I tried
improving the test via changing one of the lines, so I linted it all
together.

This closes a couple of potential exploit scenarios.
Backtick (`) for older IEs and equals (=) for unquoted attributes.

Refs 83b8e846a3
Closes https://github.com/janl/mustache.js/pull/388

This fixes a small blooper introduced in a3f4339.
Error message thrown for invalid template type, should be equal on
the server and in the browser.

As we require the template to be a `string` we now throw an error when given
any other data type. This should provide the developers with a meaningful
error rather than a cryptic TypeError from the murky depths of our source code.

Fixes #464

Fixes #445

Fixes #442

Covers the project with browser tests, not only V8 via node/iojs. Tests are runned with [zuul](https://github.com/defunctzombie/zuul) which
provides simple local browser testing, aswell as cloud testing on multiple browsers with [saucelabs](http://saucelabs.com).

+ minor fix for better error message when running specific render test

Fixes #415

Fixes #431

CLI used to render a mustache template with a data view, writes the template into stdout when successfull. Otherwise meaningfull errors into stderr.

Fixes #424

Removed cache* functions altogether. mustache.parse is all that's
really needed.

Fixes #321

Fixes #322
Fixes #330
Fixes #331
Fixes #334

Fixes #274

Fixes #267

Issue: If I create a Mustache lambda to return numbers and I expect 0 to be of
those numbers, I'll instead only receive an empty string for 0 because it
evaluates to falsy.

Fix: Check the result of the lambda to be undefined or null. Only then should
it return the empty string.

Fixes #258

Fixes #247

Text tokens now accurately reflect their content's exact position
in the original template.

Fixes #187