* metrics/prometheus: added prometheus http server and metrics collector
* metrics/prometheus: minor cleanups
* metrics/prometheus: named keys instead name in tag
* metrics/prometheus: minor typo cleanups, sorted report
* cmd/swarm: minor cli flag text adjustments
* swarm/api/http: sticky footer for swarm landing page using flex
* swarm/api/http: sticky footer for error pages and fix for multiple choices
* cmd/swarm, swarm/storage, swarm: fix mingw on windows test issues
* cmd/swarm: update description of swarm cmd
* swarm: added network ID test
* cmd/swarm: support for smoke tests on the production swarm cluster
* cmd/swarm/swarm-smoke: simplify cluster logic as per suggestion
* swarm: propagate ctx to internal apis (#754)
* swarm/metrics: collect disk measurements
* swarm/bmt: fix io.Writer interface
* Write now tolerates arbitrary variable buffers
* added variable buffer tests
* Write loop and finalise optimisation
* refactor / rename
* add tests for empty input
* swarm/pss: (UPDATE) Generic notifications package (#744)
swarm/pss: Generic package for creating pss notification svcs
* swarm: Adding context to more functions
* swarm/api: change colour of landing page in templates
* swarm/api: change landing page to react to enter keypress
This commit adds all changes needed for the merge of swarm-network-rewrite.
The changes:
- build: increase linter timeout
- contracts/ens: export ensNode
- log: add Output method and enable fractional seconds in format
- metrics: relax test timeout
- p2p: reduced some log levels, updates to simulation packages
- rpc: increased maxClientSubscriptionBuffer to 20000
* metrics: expvar support for ResettingTimer
* metrics: use integers for percentiles; remove Overall
* metrics: fix edge-case panic for index-out-of-range
* core: Add metrics collection for transaction events; replace/discard for pending and future queues, as well as invalid transactions
* core: change namespace for txpool metrics
* core: define more metrics (not yet used)
* core: implement more tx metrics for when transactions are dropped
* core: minor formatting tweeks (will squash later)
* core: remove superfluous meter, fix missing pending nofunds
* core, metrics: switch txpool meters to counters
