gosnmp.go: Added GetBulk and GetNext functions. Updated SnmpPacket struct with NonRepeaters and MaxRepetitions fields for GetBulk.
marshal.go: Added support for GetBulk and GetNext request types. Renamed unmarshalGoResponse to unmarshalResponse as it handles getnext and getbulk as well.
marshal_test.go: Added packet dumps for getnext and getbulk requests and responses. Unmarshal tests pass for both. Working on enmarshal tests still.
added packet dumps for response and request for getnext
added unmarshal test for getnext response bytes
added packet dumps for getbulk request and response
added unmarshal test for getbulk response bytes
added fields to SnmpPacket struct for getbulk (non repeaters, max repetitions)
added support for getbulk in unmarshal functions
renamed unmarshalGetResponse to unmarshalResponse as it used for all currently implemented types
added GetNext function; uses same 'infrastructure' as get so accepts multiple oids at once
added GetBulk function; uses same 'infrastructure' as Get so accepts multiple oids at once
Merge branch 'master' of https://github.com/jdubinsky/gosnmp
fixed conflicts

Conflicts:
	gosnmp.go
	marshal.go
	marshal_test.go
removed old enmarshal test