Fixed config type of $upload.http()

$upload.http() is used to send the file binary or any data to the server through the 'data' field in the config object, not the 'file' field. Hence, its config type should be just ng.IRequestConfig, and not ng.IFileUploadConfig

angular-file-upload/angular-file-upload.d.ts

@@ -9,7 +9,7 @@ declare module ng.angularFileUpload  {
 
     interface IUploadService {
 
-        http<T>(config: IFileUploadConfig): IUploadPromise<T>;
+        http<T>(config: ng.IRequestConfig): IUploadPromise<T>;
         upload<T>(config: IFileUploadConfig): IUploadPromise<T>;
     }
 
@@ -23,4 +23,4 @@ declare module ng.angularFileUpload  {
         file: File;
         fileName?: string;
     }
-} 
+}