Adds an option to use StubRunner from classpath (#284)

without this change there's no option to use Stub Runner to pick stubs from classpath
with this change we're adding that option. It's enough for the user not to provide neither the `repositoryRoot` nor `workOffline`. If that's the case then Classpath scanning will take place.

fixes #282

samples/standalone/restdocs/http-client/src/test/java/com/example/loan/LoanApplicationServiceusingStubRunnerTests.java

@@ -0,0 +1,58 @@
+package com.example.loan;
+
+import com.example.loan.model.Client;
+import com.example.loan.model.LoanApplication;
+import com.example.loan.model.LoanApplicationResult;
+import com.example.loan.model.LoanApplicationStatus;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.cloud.contract.stubrunner.spring.AutoConfigureStubRunner;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+@AutoConfigureStubRunner(ids = "com.example:http-server-restdocs")
+public class LoanApplicationServiceusingStubRunnerTests {
+
+	@Autowired LoanApplicationService service;
+	@Value("${stubrunner.runningstubs.http-server-restdocs.port}") int port;
+
+	@Before
+	public void setup() {
+		this.service.setPort(this.port);
+	}
+
+	@Test
+	public void shouldSuccessfullyApplyForLoan() throws Exception {
+		// given
+		LoanApplication application = new LoanApplication(new Client("1234567890"),
+				123.123);
+		// when:
+		LoanApplicationResult loanApplication = service.loanApplication(application);
+		// then:
+		assertThat(loanApplication.getLoanApplicationStatus())
+				.isEqualTo(LoanApplicationStatus.LOAN_APPLIED);
+		assertThat(loanApplication.getRejectionReason()).isNull();
+	}
+
+	@Test
+	public void shouldBeRejectedDueToAbnormalLoanAmount() throws Exception {
+		// given:
+		LoanApplication application = new LoanApplication(new Client("1234567890"),
+				99999);
+		// when:
+		LoanApplicationResult loanApplication = service.loanApplication(application);
+		// then:
+		assertThat(loanApplication.getLoanApplicationStatus())
+				.isEqualTo(LoanApplicationStatus.LOAN_APPLICATION_REJECTED);
+		assertThat(loanApplication.getRejectionReason()).isEqualTo("Amount too high");
+	}
+
+}