Caba simulator flags

When running caba simulator, you may specify the following flags:

• -t for creating a trace file (vcd) for use with GtkWave?
• -f <name> for specifying an alternate vcd trace file name (default is system_trace.vcd)
• -c <number> for only running for counted cycles
• -e endless simulation, never stop
• -d <number> print statistics about simulation evey n cycles, default is 100000