Glitter: implement aggregate ops: count(*), count(distinct *) and group by clause

(In [449]) addresses #16 reviewer: lee

Baseline (brute force) implementation of SELECT COUNT(*) in glitter: count results in-memory after solution generator has returned results.

(In [450]) addresses #16 reviewer: lee

Add support for COUNT(DISTINCT *) to glitter. Also add test and modify COUNT(*) to make sure it is counting non-distinct results.

comment 2 is incorrect. Should say: .and modify COUNT(*) TEST to make sure it is counting...

Plan is to add GROUP BY support next.

Re [449]

(1) The JavaDoc? for the reduced parameter in the Projection constructor got split up by countAll.

(2) Would be good for the test to make sure that the count is a typed literal with datatype xsd:integer.

(In [460]) addresses #16 reviewer: lee

Add support for GROUP BY to glitter.

(In [461]) addresses #16 reviewer: lee

fix javadoc, add datatype integer check for count per comment 4 on ticket #16.

lee, would you review the group by changes and close ticket if satisfied? thanks!

(In [462]) addresses #16 and #34 and #35 and #36 reviewer: lee

Fix big mess. r461 should have broken build but not all regressions tests were being run. This commit increases the amount of regressions tests we run. For regression tests that we cannot run I have opened tickets (#34, #35, #36). Also fixed bug in my code that should have caused build to fail: dataType for count was xsd:int, not xsd:integer. Lastly, sneek in proper hash code stuff for GroupByProjection?.

This all looks good.

To note for the future: instead of dragging BigIntegers? into the picture to get xsd:integers, you can just use the 2 argument form of the TypedLiteral? constructor and pass in an int (or a string) and use the 2nd arg to type it as an xsd:integer.