[Feature] Allow to register metric symbols from multimap
[Feature] Allow to register metric symbols from multimap

AlexeySa/rspamd,AlexeySa/rspamd,minaevmike/rspamd,AlexeySa/rspamd,minaevmike/rspamd,AlexeySa/rspamd,minaevmike/rspamd,minaevmike/rspamd,AlexeySa/rspamd,minaevmike/rspamd,AlexeySa/rspamd,minaevmike/rspamd,minaevmike/rspamd,minaevmike/rspamd,AlexeySa/rspamd,minaevmike/rspamd,AlexeySa/rspamd,AlexeySa/rspamd