Support Zabbix 6

[OrangeDog]

The Zabbix API has breaking changes in version 6.

The first problem is that the login request has changed, so none of Salt's methods get any further.

https://www.zabbix.com/documentation/6.0/en/manual/api

[q1x]

Working on this in #12 , you should be able to test from the devel branch soon.

[q1x]

Need to verify if we are impacted by the following API changes:

5.4

• ZBXNEXT-6868 hostgroup.massupdate: hosts and templates fields are now required.
• ZBXNEXT-6868 hostgroup.massadd, hostgroup.massupdate, hostgroup.massremove: added strict validation of the method parameters.
• ZBXNEXT-6867 template.create, template.update, template.delete, template.massadd, template.massupdate, template.massremove: added strict validation of the methods parameters.
• ZBXNEXT-6867 template.create, template.update, template.massadd, template.massupdate: dropped support of parameter hosts.
• ZBXNEXT-6867 template.massremove: dropped support of parameter hostids.
• ZBXNEXT-6755 message template object: added support of conditiontype value: 4 - (event created on service status update).
• ZBXNEXT-6866 usergroup.create, usergroup.update: userids parameter is now deprecated. Use users instead.
• ZBXNEXT-6718 added new method user.unblock.
• ZBXNEXT-4029 user.create, user.update: implemented password strength validation according the password policy.