Add timeout monitor for Bluetooth connections.

bramble-api/src/main/java/org/briarproject/bramble/api/io/TimeoutMonitor.java

@@ -0,0 +1,8 @@
+package org.briarproject.bramble.api.io;
+
+import java.io.InputStream;
+
+public interface TimeoutMonitor {
+
+	InputStream createTimeoutInputStream(InputStream in, long timeoutMs);
+}

bramble-api/src/main/java/org/briarproject/bramble/api/system/Clock.java

@@ -11,6 +11,11 @@ public interface Clock {
 	 */
 	long currentTimeMillis();
 
+	/**
+	 * @see System#nanoTime()
+	 */
+	long nanoTime();
+
 	/**
 	 * @see Thread#sleep(long)
 	 */

bramble-api/src/test/java/org/briarproject/bramble/test/ArrayClock.java

@@ -16,6 +16,11 @@ public class ArrayClock implements Clock {
 		return times[index++];
 	}
 
+	@Override
+	public long nanoTime() {
+		return times[index++] * 1_000_000;
+	}
+
 	@Override
 	public void sleep(long milliseconds) throws InterruptedException {
 		Thread.sleep(milliseconds);

bramble-api/src/test/java/org/briarproject/bramble/test/SettableClock.java

@@ -17,6 +17,11 @@ public class SettableClock implements Clock {
 		return time.get();
 	}
 
+	@Override
+	public long nanoTime() {
+		return time.get() * 1_000_000;
+	}
+
 	@Override
 	public void sleep(long milliseconds) throws InterruptedException {
 		Thread.sleep(milliseconds);