Introduced Error Message to Task Execution

To provide the ability to control task orchestration via the exit
message, we moved the stack trace storage to a new field.  This means
that exit message is now a field we can use similar to how exit code is
in batch, and still have the stack trace of an unsuccessful task
execution stored.

Resolves spring-cloud/spring-cloud-task#186

Disabled integration tests by default

Just some cleanup on merge

spring-cloud-task-samples/timestamp/pom.xml

@@ -52,6 +52,14 @@
 			<artifactId>spring-boot-configuration-processor</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-jdbc</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>com.h2database</groupId>
+			<artifactId>h2</artifactId>
+		</dependency>
 	</dependencies>
 
 	<build>