use default OID if missing in model
alternative method to detect remote devices

Ok, we tried to find the remote devices using dot1dTpFdbAddress without success,
let's try by using dot1qTpFdbPort this time. This alternative solution is known
to work at last with Juniper ex2200 devices.
Merge branch '2.3.x' of git+ssh://forge.fusioninventory.org/git/fusioninventory/agent into 2.3.x+juniper-fixes
Merge branch '2.3.x+juniper-fixes'
Merge branch 'master' of git+ssh://forge.fusioninventory.org/git/fusioninventory/agent
Merge remote-tracking branch 'origin/master'
data is in $self, not %params
Merge remote-tracking branch 'forge/master'
needs English for $EXTENDED_OS_ERROR
rename “cpt” to “_cpt” to avoid ambiguity
use context-dependant SNMP default timeout

See commit #e25c2c8 for details
test getCanonicalMacAddress()
deal with vlan_id in MAC address
convert unpacked result to canonical MAC
MAC in binary format
indent
partial rewrite of port/MAC detection code
test setConnectedDevicesMacAddresses()
compute the correct number of test
“timeout” is a parameter