build: i18n: fix build on OSX

Fix config option that doesn't work with OSX.

Fixes: https://github.com/joyent/node/issues/8521
PR-URL: https://github.com/joyent/node/pull/8602
Reviewed-by: Trevor Norris <trev.norris@gmail.com>
build: i18n: fix icu toolset dependencies

So what I did here is to make the icutools library actually contain the
entire ICU dependencies needed for host-side tools. Sadly, this will
build ICU twice, but avoids conflicts between host and target side.
This all seems like a gyp bug of some sort, but without docs for
toolsets, who’s to say?

I removed the icuio library as a separate target, because it was only
used by the host-side tools.

PR-URL: https://github.com/joyent/node/pull/8681
Reviewed-by: Trevor Norris <trev.norris@gmail.com>
build: i18n: support little-endian machines

Note that this may not affect anything until powerpc support lands in
v8.

Related: https://github.com/srl295/node/issues/7
Related: https://github.com/srl295/node/commit/ba8ab91bc4762ade646474276c4a4b8cdaf83115
PR-URL: https://github.com/joyent/node/pull/8712
Reviewed-by: Trevor Norris <trev.norris@gmail.com>
module: correct the order of the assertions

this puts the type-checking assertions in require
into proper order.

PR-URL: https://github.com/joyent/node/pull/8333
Reviewed-by: Chris Dickinson <christopher.s.dickinson@gmail.com>
Reviewed-by: Fedor Indutny <fedor@indutny.com>