Handle file uploads in AngularJS.md

• https://github.com/danialfarid/angular-file-upload
• https://github.com/twilson63/ngUpload
• http://blueimp.github.io/jQuery-File-Upload/angularjs.html
• http://blog.brunoscopelliti.com/a-directive-to-manage-file-upload-in-an-angularjs-application
• http://badwing.com/multipart-form-data-ajax-uploads-with-angularjs/
• http://shazwazza.com/post/Uploading-files-and-JSON-data-in-the-same-request-with-Angular-JS
• http://flowjs.github.io/ng-flow/
• http://uncorkedstudios.com/blog/multipartformdata-file-upload-with-angularjs
• http://badwing.com/multipart-form-data-ajax-uploads-with-angularjs/