No subject

[Lawrence L Love]

This patch is to allow multiple --calls=<...> or --frames=<...> in a
single command line to apitrace.

A different implementation would be to put a check for the first
--calls/--frames occurence during the command line parsing in order
to initialize the CallSet object the first time. That may be clearer
in reading the code but I thought it would be better to contain the
logic in the object and may be less error prone in maintainablity

Larry