Improve timeslice bookkeeping/monitoring

[cuveland]

Improve the monitoring output of the tsclient binary concerning timeslice bookkeeping.

• Add monitoring output to the new ManagedTimesliceBuffer class.
• Tags:
  • host: hostname
  • shm: name of shared memory
• Fields:
  • buf_ts: number of timeslice in the shm buffer
  • buf_fill: buffer utilization (use minimum of space available)
  • ts_done: timeslices processed (since start of run)
  • ts_lost: timeslices lost (assuming round-robin distribution, calibrate stride using first two timeslices)