yaml os discovery now respects the os mib_dir definition
mib_dir now only allows strings, not arrays
changed schema validation to account for that
consolidated dell mibs, no reason for them to be spread out
* OS detection for Dell PowerVault MD arrays
I'm not 100% sure it was worth Dell implementing SNMP - the array
exposes 6 OID's outside of MIBII, and we poll both the useful ones.
At least we get an icon.
* Test data
* Remove polling and discovery module filters
Current implementation for Force10 series doesn't support the switch-blade M-Series model. This PR adds support for mempools and temperature. In my test environment (still 1.31) I have processors utilization support as well, but I have to test that in the new way processors are handled since 1.37
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