Summary:
Adding support for downloading archived Flipper data using a URL handler.
A URL looks like `flipper://import/?url=` and will download the file specified in the url param. While downloading the file, a spinner is shown in the app's titlebar.
Reviewed By: jknoxville
Differential Revision: D14262763
fbshipit-source-id: 6538fc78c07a48cef7b71b3f7bdbcb712d054593