* Added snmp_max_oid config at Os level.
* Added check for snmpv1 on multi_oid requests.
* Check device_oid_limit on multi get
* Use array_chunk
* Update snmp.inc.php
* remove dump, unused variable and extra plodes
* per device settings should take priority over OS
* Update Settings.md
* don't discard the data :P
Changed some values to be explicitly boolean
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* refactor: speed up is_valid_port()
Convert is_valid_port to Config
Several Config optimizations
Update documentation
* fix getCombined() when os key is not set, but global is.
Add more tests
* feature: Allow ignore_mount, ignore_mount_string, ignore_mount_regex at OS level
* Change the storage settings to override global instead of merge.
Add documentation
