Introduced new stage.
Introduced new Filterer.
Now creating filter output.
Started implementing Filter.
Added new pattern abstraction class.
Build new pattern abstraction to replace boolean[] and prepare POS and DEL counting.
Reverted filter.
Fixed a case where continuation counting was different from master.
Small bug with PatternType#fromString.
Renamed PatternType to PatternElem.
Merge branch 'feature/extractingBeforeCounting' into develop. Result is
that extract is still happening after counting, but new pattern
abstraction is added.