More SmartOS esky fixes

bbfreeze doesn't find pipes module for 0.17.5 which breaks
the git module (someone should check this for Linux and Windows)
(Interestingly it does find it in the 2014.1.0rc3 build)

Also, SmartOS should eventually get the spwd module
so we should try to import and include it like we do for Linux
( see https://github.com/joyent/pkgsrc/issues/164 )