Merge pull request #162 from wgerlach/master

new download function that simplifies code
If download_post is used to copy a node to another Shock server and "Authorization" is included in the header of the GET request, that Authorization header will now be passed onto the secondary Shock server to which the node is being copied.
Merge pull request #163 from jaredbischof/master

If download_post is used to copy a node to another Shock server and "Aut...
Merge branch 'master' of https://github.com/MG-RAST/Shock