Start adoption of executable test finder

src/testing/Model/CUTESuite.ts

src/testing/Model/CUTETest.ts

src/testing/Model/TestElement.ts

src/testing/Model/TestTree.ts

src/testing/ResultAnalyzer/ResultAnalyzer.ts

src/testing/ResultAnalyzer/XMLResultAnalyzer.ts

src/testing/TestFinder.ts

src/testing/TestFinder/CodeTestFinder.ts

src/testing/TestFinder/ExecutableTestFinder.ts

src/testing/TestFinder/TestFinder.ts

src/utilities/ExecutableSpawner.ts