File permissions
Added script to create virtualenv script
Allow specifying --trait-col for association results

If association results already has a trait column, we can use it instead
of directly specifying the --trait. This is useful in the scenario where
you lump together results for multiple traits into a single file, to
pick lead SNPs at each locus by which trait has the strongest
association.
Merge branch 'master' of https://github.com/welchr/Swiss