multisocket plugin (#6882)

* multisocket plugin improves performance in multiprocessor systems

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* - refactoring
- update doc

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* remove port from reuseport plugin README

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* rename reuseport plugin to numsockets plugin

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* Add Recommendations to numsockets README

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* added numsockets test; made NUM_SOCKETS mandatory in doc

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* restart and whoami tests for numsockets plugin

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* default value for numsockets

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* caddy up

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* add numsockets to plugin.cfg

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* - rename numsockets plugin to multisocket
- default as GOMAXPROCS
- update README

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

* resolve conflicts

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

---------

Signed-off-by: Viktor Rodionov <33463837+Shmillerov@users.noreply.github.com>

plugin.cfg

@@ -25,6 +25,7 @@ geoip:geoip
 cancel:cancel
 tls:tls
 timeouts:timeouts
+multisocket:multisocket
 reload:reload
 nsid:nsid
 bufsize:bufsize