Wrong Firmware Discovery for microsens G6 devices and missing temperature sensor

Hi there,

I noticed that $config['mibs'][$mib]['version'][] references the wrong MIB in includes/definitions/mibs/microsens.inc.php.

Attached is a patch that corrects this by updating the line to use the appropriate G6-SYSTEM-MIB.

Additionally, the temperature is not being detected correctly. I'm not sure what's going on. The debug output shows:
 o G6-SYSTEM-MIB        systemTemperature [
CMD[/usr/bin/snmpbulkwalk -v2c -c *** -Pud -Ih -OQUsb -m G6-SYSTEM-MIB -M /srv/observium/mibs/rfc:/srv/observium/mibs/net-snmp:/srv/observium/mibs/microsens 'udp':'host':'161' systemTemperature]CMD EXITCODE[0]
CMD RUNTIME[0.5734s]
STDOUT[
systemTemperature = No Such Instance currently exists at this OID
]
SNMP STATUS[FALSE]
SNMP ERROR1000 - Failed response
{{] }}

The value for system temperature is available at systemTemperature.0. However, after updating microsens.inc.php accordingly, I get the following result:

 o G6-SYSTEM-MIB        systemTemperature.0 [
CMD[/usr/bin/snmpbulkwalk -v2c -c *** -Pud -Ih -OQUsb -m G6-SYSTEM-MIB -M /srv/observium/mibs/rfc:/srv/observium/mibs/net-snmp:/srv/observium/mibs/microsens 'udp':'x-sw1016.lan.est1816.de':'161' systemTemperature.0]CMD EXITCODE[0]
CMD RUNTIME[0.116s]
STDOUT[
systemTemperature.0 = 38
]
SNMP STATUS[TRUE]
Store in cache Table OID: G6-SYSTEM-MIB::systemTemperature.0
Excluded by sensor 'systemTemperature.0' value '' is not numeric.
]