Add metrics to replace data extracted from logging

[bbangert]

Data points to track with metric counters:

• message.(jwt_sub)
• Split out hit/miss
• Bridge protocol message stats
• Bridge churn
• Invalid token counter
• Error codes and errno's
• Message destination
• Message size

Data points to track with timers:

• Request timings that are currently done in a 'Request timings' message
• Latency to route to online nodes