add() Function Unit Test

Signed-off-by: Lee <jessy1092@gmail.com>
multiply() function unit test.
divide() function unit test.
minus() function unit test.
stringSplit() function unit function.
mapID() function unit test.
mod() function unit test.
Add IdCompute unit test.
Imp mod function. #7
yo~, issue #4
Add string split, issue #5
Adding Finished, issue #1
Hotfix, issue 3
finish multiply, issue #2
LEE is a good teacher, issue #6
Hotfix issue #3
Merge pull request #10 from WebStudyTW/feature/multiply

Feature/multiply
Merge branch 'feature/add' into develop

* feature/add:
  Adding Finished, issue #1
  add() Function Unit Test

Conflicts:
	test/test_computeUtil.js
fix test.
Merge branch 'feature/divide' into develop

* feature/divide:
  Hotfix issue #3
  Hotfix, issue 3
  divide() function unit test.

Conflicts:
	lib/ComputeUtil.js
	test/test_computeUtil.js