* * Add DimensionSelector.idLookup() and nameLookupPossibleInAdvance() to allow better inspection of features DimensionSelectors supports, and safer code working with DimensionSelectors in BaseTopNAlgorithm, BaseFilteredDimensionSpec, DimensionSelectorUtils;
* Add PredicateFilteringDimensionSelector, to make BaseFilteredDimensionSpec to be able to decorate DimensionSelectors with unknown cardinality;
* Add DimensionSelector.makeValueMatcher() (two kinds) for DimensionSelector-side specifics-aware optimization of ValueMatchers;
* Optimize getRow() in BaseFilteredDimensionSpec's DimensionSelector, StringDimensionIndexer's DimensionSelector and SingleScanTimeDimSelector;
* Use two static singletons, TrueValueMatcher and FalseValueMatcher, instead of BooleanValueMatcher;
* Add NullStringObjectColumnSelector singleton and use it in MapVirtualColumn
* Rename DimensionSelectorUtils.makeNonDictionaryEncodedIndexedIntsBasedValueMatcher to makeNonDictionaryEncodedRowBasedValueMatcher
* Make ArrayBasedIndexedInts constructor private, replace it's usages with of() static factory method
* Cache baseIdLookup in ForwardingFilteredDimensionSelector
* Fix a bug in DimensionSelectorUtils.makeRowBasedValueMatcher(selector, predicate, matchNull)
* Employ precomputed BitSet optimization in DimensionSelector.makeValueMatcher(value, matchNull) when lookupId() is not available, but cardinality is known and lookupName() is available
* Doc fixes
* Addressed comments
* Fix
* Fix
* Adjust javadoc of DimensionSelector.nameLookupPossibleInAdvance() for SingleScanTimeDimSelector
* throw UnsupportedOperationException instead of IAE in BaseTopNAlgorithm