danialfarid/angular-file-upload — pull request #90 by madhurjain (2013-12-31 14:31:05+00:00)
Title: Fixed TypeError: Cannot set property 'Content-Type' of undefined

In the latest version of angular-file-upload while using `$upload.upload({ .. });` method
throws a *TypeError: Cannot set property 'Content-Type' of undefined.*

This issue was introduced in the recent commit dc0ef88ae44d9e5 when `$upload.http` method was added

This pull request fixes the issue by just initializing the `config.headers` to empty object in upload function definition

config.headers = config.headers || {};