Close writer

- Make sure PrintWriter is closed after
  yaml dump
- While fixing obvious file handle leak makes
  junit's temp dir deletion to work
- Fixes #187

Author: jvalkeal

src/main/java/org/springframework/cli/roles/RoleService.java

@@ -84,8 +84,8 @@ public void updateRole(String roleName, String key, Object value) {
 		dumperOptions.setLineBreak(DumperOptions.LineBreak.getPlatformLineBreak());
 		Yaml yaml = new Yaml(dumperOptions);
 		File getRoleFile = getFile(roleName);
-		try {
-			yaml.dump(map, new PrintWriter(getRoleFile));
+		try (PrintWriter writer = new PrintWriter(getRoleFile)) {
+			yaml.dump(map, writer);
 		}
 		catch (FileNotFoundException ex) {
 			throw new SpringCliException(