This change:
- Ports the nginx benchmark.
- Switches the Httpd benchmark to use 'hey' as a client.
- Moves all parsers to their own package 'tools'.
Parsers are moved to their own package because 1) parsing output of a command
is often dependent on the format of the command (e.g. 'fio --json'), 2) to
enable easier reuse, and 3) clean up and simplify actual running benchmarks
(no TestParser functions and ugly sample output in benchmark files).
PiperOrigin-RevId: 324144165
Zach Koopmans