named container ports should have sane env var names

Resolves problems like this:

    EnvVar.Name: invalid value 'RM_PORT_abc-def_TCP' 
    EnvVar.Name: invalid value 'RM_PORT_abc-def_TCP_PROTO' 
    EnvVar.Name: invalid value 'RM_PORT_abc-def_TCP_PORT' 
    EnvVar.Name: invalid value 'RM_PORT_abc-def_TCP_ADDR'