PCT-506 Fixed lost sample
PCT-808: init, WIP
PCT-808: Don't include pt-{mysql-,}summary, use it like dependency
PCT-808: implement pt-mysql-summary
PCT-808: rename service name to "pt"; register manager in agent
PCT-808: clean up; actually register pt-manager
PCT-808: cleanup in cmd package, export errors
PCT-808: more cleanups
PCT-808: Tests to assure we properly map DSN params to pt-mysql-summary params
PCT-808: Proper handling of error when PT is not in the path
+ tested if this changes in the future
PCT-808: By default sleep 4s, for some reasons pt-mysql-summary is aborted after 9s
(probably it is aborted in front-end?)
PCT-808: Include better output structure + fix tests
PCT-808: lock error message "Executable file not found in $PATH" with tests
PCT-808: cleanup + fix usage of logger (didn't expect such behaviour)
PCT-808: workaround for "HOME: parameter not set" error on jenkins + simplify cmd
PCT-808: drop std err from output
PCT-565 Protection from invalid caputure

Added a control of time took to collect the metrics.
If it is > 10% of ticker interval, metrics are discarded.
The calculated time include all metrics collected in the run function
because ie if SHOW STATUS takes 3 seconds, all following metrics like
SELECT NAME, ... FROM INFORMATION_SCHEMA.INNODB_METRICS will be
timeshifted, so I think we need to ignore them to keep them synchronized.
Add pct.Cmd to test agent restart.
Remove, don't send empty data files (PCT-764). Fix ws client and how data.Sender and log.Relay use it. Increase and improve testing in log, data, and agent. Add trash to basedir and data.Spooler.Reject (not used yet). Fix pct.WaitStartLock().
Add trash dir to basedir. Fix percona-agent/main.go.