Ticket 66 - Nunc-stans requires c99
    
    Bug Description:  Build doesn't work on el7 because we are using c99 features
    and rhel7 defaults to c99.
    
    Fix Description:  Add the correct stanzas to configure.ac to enable this.
    
    https://fedorahosted.org/nunc-stans/ticket/66
    
    Author: wibrown
    
    Review by: nhosoi