pathos: add pp-1.5.7-pathos-3 using getimportable instead of getsource
dill: add 'explicit' to getimportable and likely_import for builtin functions


git-svn-id: svn+ssh://svn.mystic.cacr.caltech.edu/pathos/pathos@624 8bfda07e-5b16-0410-ab1d-fd04ec2748df
pathos: added license and copyright to each file;
deleted empty directories


git-svn-id: svn+ssh://svn.mystic.cacr.caltech.edu/pathos/pathos@628 8bfda07e-5b16-0410-ab1d-fd04ec2748df
Merge branch 'master' of https://github.com/uqfoundation/pathos