Use same names as vpn examples

src/freedombone-app-vpn

 IN_DEFAULT_INSTALL=0
 SHOW_ON_ABOUT=0
 
-OPENVPN_SERVER_NAME="${PROJECT_NAME}-vpn"
-OPENVPN_KEY_FILENAME='vpn.ovpn'
+OPENVPN_SERVER_NAME="server"
+OPENVPN_KEY_FILENAME='client.ovpn'
 
 vpn_variables=(MY_EMAIL_ADDRESS
                MY_USERNAME)