Parse Apache log etime and display average per command
    
    Including execution time (etime) was added in commit
    4d716d3fbc69760bc0f7bd1a7c83ab14f1a62f18
    
    This is a parser that will collect API executions and
    average them by command.
    
    If > 5 requests of the same type then the fastest and slowest
    results will be dropped to try to smooth the average.
    
    These averages will be used for two purposes:
    
    1. Identify potential bottlenecks in API performance
    2. Provide a baseline so that future performance changes can be
       measured.
    
    It is included in contrib because this is not going to be shipped
    with a distribution but is useful to have with the code.
    
    A sample execution is:
    
    Successful commands:
     Mean user_show: 12234152.5 of 2 executions
     Mean command_defaults: 3284363.0 of 3 executions
     Mean user_add: 594369554.5 of 2 executions
    Exceptions:
     Mean user_del: 232540327 ns of 2 executions
    The parselog command was successful
    
    Times are in nanoseconds.
    
    https://pagure.io/freeipa/issue/8809
    
    Signed-off-by: Rob Crittenden <rcritten@redhat.com>
    Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>