Set $(paths.path[npm]) and $(paths.path[pip]) to the correct path on darwin and
freebsd

Set $(paths.path[getfacl]) to the correct path on freebsd
Set the default value of $(paths.path[getfacl]) to '/usr/bin/getfacl'
on all platforms except freebsd and darwin
Merge pull request #320 from skreuzer/pip

Fix path to npm, pip and getfacl