Method registerCom

\brief Register a command with this interface A command object is associated with one or more tokens on the command line. A string containing up to 5 tokens can be associated with the command. \param fptr is the IfaceCommand object \param nm1 is the first token representing the command \param nm2 is the second token (or null) \param nm3 is the third token (or null) \param nm4 is the fourth token