Update README file

README.md

@@ -52,11 +52,26 @@ Filestack uses multipart uploading by default, which is faster for larger files.
 ```ruby
 filelink = client.upload(filepath: '/path/to/file')
 
+filelink = client.upload(filepath: '/path/to/file', multipart: false)
+
 # OR
 
 filelink = client.upload(external_url: 'http://someurl.com')
 ```
 
+To upload a local and external file with query parameters:
+```ruby
+filelink = client.upload(filepath: '/path/to/file', options: {mimetype: 'image/png'})
+
+filelink = client.upload(external_url: 'http://someurl.com/image.png', options: {mimetype: 'image/jpeg'})
+```
+
+To store file on `dropbox`, `azure`, `gcs` or `rackspace`, you must have the chosen provider configured in the developer portal to enable this feature. By default the file is stored on `s3`.
+```ruby
+filelink = client.upload(filepath: '/path/to/file', storage: 'dropbox', options: {path: 'folder_name/'})
+
+filelink = client.upload(external_url: 'http://someurl.com/image.png', storage: 'dropbox', options: {path: 'folder_name/'})
+```
 ### Security
 If security is enabled on your account, or if you are using certain actions that require security (delete, overwrite and certain transformations), you will need to create a security object and pass it into the client on instantiation.