Fix trim option for empty tags

[AHarman]

Previously, this test would fail:

'test trimming on empty tag with whitespace': skeleton(trim: true, (r) ->
    equ r.sample.emptytestanother[0], '')

where "emptytestanother" looked like this:

    <emptytestanother>

    </emptytestanother>

The value was coming back as \n \n (the whitespace between the tags).

[Leonidas-from-XIV]

Can you add the test and implement the fix in the CoffeeScript source code?

[AHarman]

Sorry about that! Committed the wrong files.

I've fixed that and pushed the right changes.