Concatenation is good
update .gitignore
USpan function interface
Implement little
Small change
Update string to int
Merge branch 'jhow-dev' into Johnny
Merge branch 'Johnny' into jhow-dev
Find matched(pivot, end item) flow ok
Modify depth pruning flow
Width pruning flow ok
Small update
Merge branch 'Johnny' of https://github.com/jhowliu/DataMining into Johnny
Merge branch 'Johnny' into jhow-dev
Candiate generate flow ok
Compile ok
Fix I-Concat Width pruning
(Check pivot and all the end item)
Add I/S-Concatenation and utility calculation.
Merge branch 'Johnny' of https://github.com/jhowliu/DataMining into Johnny
Merge branch 'jhow-dev' into Johnny

Conflicts:
	function.cpp