Add alarm support to OpenOMCI-lib-go

To help simplify Alarm/Alarm Manager support on the OpenONU-go adapter, add alarm information to the generated OMCI code.  Alarm extraction is already supported by the adapter and basic additions to the golang template can help autogen this support.
 
In the ManagedEnitityDefinition add 'AlarmMap'  that is a mapping of alarm bit numbers to the alarm name.   On Rx of an alarm notification, get the ME definition and if the AlarmMap attribute is not 'nil', then you can use it to look up the alarm bits and names.     So the ManagedEntityDefinition would look like:
// ManagedEntityDefinition defines a Manage Entity
type ManagedEntityDefinition struct {
Name string
ClassID ClassID
MessageTypes mapset.Set // Mandatory
AllowedAttributeMask uint16
AttributeDefinitions AttributeDefinitionMap
Access ClassAccess
Support ClassSupport Alarms map[uint]string // Alarm Bit -> Alarm Name !! THIS IS NEW{color}}
 

And the ME's that support any alarms will have something like the following added.  (Note that this may not be a one-to-one match with the names in python to start with).



Access: CreatedByOnu,
Support: UnknownSupport,
Alarms: map[int]string {
0 : "LAN-LOS", !!! THIS IS NEW
},
}
 

Note:  The alarm names extracted from the G.988 document with the OMCI parser may be different than the values in the python scapy code.  If any of these text strings need to be identical for the consumers of the alarm information, this can be addressing in a different JIRA.