Add detailed peer statistics to PerfLog for both

[mtrippled]

perf_log and server_info counters.

High Level Overview of Change

Adds detailed counters and accumulators for peer traffic, including for each message type, inbound and outbound, connection attempts and failure reasons, and disconnections with reasons, for both inbound and outbound connections.

Context of Change

To aid in diagnostics and trend analysis.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactor (non-breaking change that only restructures code)
• Performance (increase or change in throughput and/or latency)
• Tests (you added tests for code that already exists, or your new feature included in this PR)
• Documentation update
• Chore (no impact to binary, e.g. .gitignore, formatting, dropping support for older tooling)
• Release

API Impact

• Public API: New feature (new methods and/or new fields)
• Public API: Breaking change (in general, breaking changes should only impact the next api_version)
• libxrpl change (any change that may affect libxrpl or dependents of libxrpl)
• Peer protocol change (must be backward compatible or bump the peer protocol version)

This data will be available in both perf_log and the server_info RPC call with the "counters" parameter passed. It can be plugged into monitoring systems that generate graphs showing peer activities over time.

[Tapanito]

A lot of the p2p traffic information, such as in/out messages received are already present in the statsd metrics exporter. To see an example of what's available, run rippled print command. Why does it have to be duplicated in the perf log file? Wouldn't it be more advantageous to use modern metrics collection, which makes it easier to ingest the metrics into grafana, than exposing them via files?