SFTP support for gate ingestion.

* Remote browser utilites class
* GateFileHandlingAction and GateFileHandlingConfiguration changes to support it
* Extend FTPActionConfiguration to allow SFTP uso on this action.
* Write a test with a FTP mocked server
* Allow to save result on another remote server via FTP/SFTP
* Make configurable remote file delete when the file was downloaded
* Make configurable if you want to check if the file already handled after download and process