Merge branch 'prometheus_metrics_part2' into prometheus_metrics

dapps/valuetransfers/dapp.go

dapps/valuetransfers/fpc.go

dapps/valuetransfers/packages/consensus/fcob.go

packages/metrics/events.go

packages/metrics/metrics.go

packages/vote/fpc/fpc.go

packages/vote/fpc/fpc_test.go

packages/vote/net/server.go

packages/vote/voter.go

plugins/metrics/events.go

plugins/metrics/fpc.go

plugins/metrics/fpc_test.go

plugins/metrics/message.go

plugins/metrics/message_test.go

plugins/metrics/parameters.go

plugins/metrics/plugin.go

plugins/metrics/value.go

plugins/metrics/value_test.go