Adicionando seção referente a configuração para uso do mecanismo de transferência via SSH.

[SOMA-2584]

README.md

@@ -47,6 +47,25 @@ following to your `sgad.cfg`:
 To use `sga-exec` when writing your own driver, the rule of thumb is to
 avoid Lua's standard `io.*` and `os.*` routines.
 
+## ssh-datatransfer
+
+A SGA daemon can use a ssh data transfer mechanism to copy input and executable files to execute on remote 
+host sandbox. The SSH data transfer configuration can be enable with posix driver. Add the following to your `sgad.cfg`: 
+    
+    driver = "sga.driver.posix"
+    extra_config = {
+        csbase_transfer_name = "ssh-datatransfer",
+        csbase_csfs_root_dir = "/tmp/csfs_sandbox",
+        ssh_host = "localhost",
+        ssh_port = 22,
+        ssh_user_name = "csgrid",
+        ssh_private_key_path = "/home/csgrid/.ssh/csgrid_id_rsa"
+    }
+
+`Note:`
+Add **csgrid_id_rsa** private key in /home/csgrid/.ssh CSGrid server directory and fill **csgrid_id_rsa.pub** 
+file content in SGA csgrid home directory _.ssh/authorized_keys_ file. 
+
 ## Install
 
 Requirements: