Add tsuid as a string to the IncomingDataPoint class for use with last data
point queries
Add Internal.GetLastDataPointCB() to parse the last data point from a row in
storage, skipping all non-datapoint values.
Fix Internal
Add RowKey.rowKeyFromTSUID() to generate a row key given a TSUID and a timestamp
Add Tags.resolveIdsAsync() to handle asynchronous ID to tag resolution. Also
added unit tests for the call
Add TSMeta.getLastPoint() to attempt to retrieve the last data point for a
given TSUID