Check split keys validity and fill in if necessary.
Check split keys validity and fill in if necessary continue.
Check split keys validity and fill in if necessary continues.
Check split keys validity and fill in if necessary bug fixes
More tests on bug.
More tests on bug.
Improve ScanRangesTest.
Improve ScanRangesTest.
Minor refactoring.
Fix skip scan intersect bugs.
Minor fix up and added couple more test.
Fix typos.
Minor refactoring.
Merge pull request #195 from tonyhuang/master

Check split keys validity and fill in if necessary and tests on ranges intersect.
Support referencing an alias in the GROUP BY and ORDER BY clauses