Add Closeable to JedisPool.

This allows JedisPool instances to also participate in try-with-resources.

Adds tests (both for JedisPool and the Jedis code itself).

src/test/java/redis/clients/jedis/tests/ConnectionCloseTest.java

@@ -0,0 +1,51 @@
+package redis.clients.jedis.tests;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Set;
+
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+import redis.clients.jedis.Connection;
+import redis.clients.jedis.exceptions.JedisConnectionException;
+
+public class ConnectionCloseTest extends Assert {
+
+	private final Closer closer = new Closer();
+
+	private Connection client;
+
+	@Before
+	public void setUp() throws Exception {
+		client = closer.register(new Connection());
+	}
+
+	@After
+	public void tearDown() throws Exception {
+		closer.close();
+	}
+
+	@Test(expected = JedisConnectionException.class)
+	public void checkUnkownHost() {
+		client.setHost("someunknownhost");
+		client.connect();
+	}
+
+	@Test(expected = JedisConnectionException.class)
+	public void checkWrongPort() {
+		client.setHost("localhost");
+		client.setPort(55665);
+		client.connect();
+	}
+
+	@Test
+	public void connectIfNotConnectedWhenSettingTimeoutInfinite() {
+		client.setHost("localhost");
+		client.setPort(6379);
+		client.setTimeoutInfinite();
+	}
+}