Alternate method of making temp data folder to account for domain-joined windows accounts #193

[kieranjol]

This is a fix for #193 and uses an alternative method (os.mkdir) instead of tempfile.mkdtemp to work correctly with domain-joined windows accounts with regards to permissions. I'm very open to any other methods of working around this issue!

[kieranjol]

It could be good to hear from @edsu as some tempfile issues arose before regarding permissions: #22 and this was the commit that introduced tempfile a7c44b5 in order to fix this issue around bag.save() #29