Update readme with new sftp_enable_selinux_support variable

README.md

@@ -26,6 +26,7 @@ The following role variables are relevant:
 * `sftp_directories`: A list of directories that need to be created automatically for each SFTP user.  Defaults to a blank list (i.e. "[]").
   * Values can be plain strings, or dictionaries containing `name` and (optionally) `mode` key/value pairs.
 * `sftp_allow_passwords`: Whether or not to allow password authentication for SFTP. Defaults to False.
+* `sftp_enable_selinux_support`: Whether or not to explicitly enable SELinux support. Defaults to False.
 * `sftp_users`: A list of users, in map form, containing the following elements:
   * `name`: The Unix name of the user that requires SFTP access.
   * `password`: A password hash for the user to login with.  Blank passwords can be set with `password: ""`.  NOTE: It appears that `UsePAM yes` and `PermitEmptyPassword yes` need to be set in `sshd_config` in order for blank passwords to work properly.  Making those changes currently falls outside the scope of this role and will need to be done externally.