Merge into master from pull request #120:

...floodlightcontroller/core/web/JacksonCustomConverter.java

...erializers/EventHistoryAttachmentPointJSONSerializer.java

...erializers/EventHistoryTopologyClusterJSONSerializer.java

...b/serializers/EventHistoryTopologyLinkJSONSerializer.java

...serializers/EventHistoryTopologySwitchJSONSerializer.java

...ler/core/web/serializers/NodePortTupleJSONSerializer.java

.../core/web/serializers/OneComponentTimeJSONSerializer.java

...r/devicemanager/internal/EventHistoryAttachmentPoint.java

...ava/net/floodlightcontroller/linkdiscovery/LinkTuple.java

...r/linkdiscovery/internal/EventHistoryTopologyCluster.java

...ller/linkdiscovery/internal/EventHistoryTopologyLink.java

...er/linkdiscovery/internal/EventHistoryTopologySwitch.java

...ntroller/linkdiscovery/internal/LinkDiscoveryManager.java

...et/floodlightcontroller/perfmon/CumulativeTimeBucket.java

...ontroller/perfmon/CumulativeTimeBucketJSONSerializer.java

...va/net/floodlightcontroller/perfmon/OneComponentTime.java

...va/net/floodlightcontroller/restserver/RestApiServer.java

...java/net/floodlightcontroller/topology/NodePortTuple.java

...a/net/floodlightcontroller/util/EventHistoryBaseInfo.java

...htcontroller/util/EventHistoryBaseInfoJSONSerializer.java