add CLIENT_FILEPATH environment variable support

This environment variable can be set to customize destination of
.ovpn file to generate.

If defined, it should contain the full path of the file to generate.

openvpn-install.sh

@@ -1093,6 +1093,7 @@ function newClient() {
 		echo "Client $CLIENT added."
 	fi
 
+	if [[ -z "$CLIENT_FILEPATH" ]]; then
 		# Home directory of the user, where the client configuration will be written
 		if [ -e "/home/${CLIENT}" ]; then
 			# if $1 is a user name
@@ -1113,6 +1114,7 @@ function newClient() {
 		fi
 
 		CLIENT_FILEPATH="$homeDir/$CLIENT.ovpn"
+	fi
 
 	# Determine if we use tls-auth or tls-crypt
 	if grep -qs "^tls-crypt" /etc/openvpn/server.conf; then