Add predictedActiveCellsList to TemporalMemoryInspectMixin
Added metric: number of predicted=>active cells per column in a given sequence
Added metric: # of sequences each predicted active cell shows up in
Added prettyPrintSequenceCellRepresentations
Update test
Added documentation and clarity
Merge pull request #1346 from chetan51/issue-1329_metrics

Add sequence metrics to TemporalMemoryInspectMixin