adding the breakdown to the user object before it

it was checking to see if the Invoice object had `USERNAME_FIELD`
had been set. Which is in incorrect.

Now it looks up to see if the `USERNAME_FIELD` is being set on the
user object.
adding .DS_Store to ignore
adding OSX section and adding .DS_Store
previously the code was checking to see if Invoice

had `USERNAME_FIELD` which it doesn't. I have updated it to
check the user model which is the intended behaviour.
Merge pull request #108 from myusuf3/master

changing all the protocols to https
adding @myusuf3 to authors
Merge pull request #109 from myusuf3/customer-user-fix

Customer User Fix
merge conflict