wanted: push :BIG-ENDIAN to *FEATURES*

[Luís Oliveira]

The attached patch pushes :big-endian to *features* when appropriate. I offer three rationales:

1. Correctness. :big-endian and :little-endian are not the only possible endianness modes, although that is admittedly rather hypothetical.

2. Practicality. trivial-features[1] decided to push :big-endian (mostly because CCL did it), a handful of libraries depend on that and we want to turn trivial-features into a no-op some day.

3. Style. If big endian is The One True Endianness, then one could argue that using #+big-endian and #-big-endian is nicer than the alternative. :-)

[1] http://cliki.net/trivial-features

[Nikodemus Siivola (nikodemus)]

Looks good to me, except for missing a commit message...

[Nikodemus Siivola (nikodemus)]

commit 32d3b398d33736e61b51a14afca8c14decec4437
Author: Luis Oliveira <email address hidden>
Date: Thu Dec 8 16:56:01 2011 +0200

    explicit :BIG-ENDIAN feature

     Instead of implying big-endianness by lack of the :LITTLE-ENDIAN feature,
     make it explicit.