update tests
tests for primarySuppression()
test-all.R uses testthat package to run unit-tests
unit-tests for protectTable()
add testcase for problems with no primary suppressions
add dependency to testthat package
loading the package is not required
applying unittests with testthat package for protectTable (fix #8 and fix #5), makeProblem (fix #6) and primarySuppression (fix #7)