Fix `Expected BEGIN_OBJECT but was BEGIN_ARRAY at path $`

[dim4o]

Steps to reproduce the bug:

1. Run the Server and Agent but don't connect Agent to Server
2. Run a test. The test will fail (expected behavior)
3. Connect Agent to Server
4. Run the test again.

The Server will throw:

VIII 04, 2017 4:15:06 PM org.glassfish.tyrus.core.AnnotatedEndpoint onError
INFO: Unhandled exception in endpoint com.musala.atmosphere.server.websocket.ClientServerEndpoint.
com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at path $
	at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:224)
	at com.google.gson.Gson.fromJson(Gson.java:887)
	at com.google.gson.Gson.fromJson(Gson.java:952)
	at com.google.gson.internal.bind.TreeTypeAdapter$GsonContextImpl.deserialize(TreeTypeAdapter.java:162)
	at com.musala.atmosphere.commons.websocket.util.deserializer.RequestMessageDeserializer.deserialize(RequestMessageDeserializer.java:53)
	at com.musala.atmosphere.commons.websocket.util.deserializer.RequestMessageDeserializer.deserialize(RequestMessageDeserializer.java:25)
	at com.google.gson.internal.bind.TreeTypeAdapter.read(TreeTypeAdapter.java:69)
	at com.google.gson.Gson.fromJson(Gson.java:887)
	at com.google.gson.Gson.fromJson(Gson.java:852)
	at com.google.gson.Gson.fromJson(Gson.java:801)
	at com.google.gson.Gson.fromJson(Gson.java:773)
	at com.musala.atmosphere.commons.websocket.util.GsonUtil.deserializeRequest(GsonUtil.java:68)
	at com.musala.atmosphere.server.websocket.ClientServerEndpoint.onJsonMessage(ClientServerEndpoint.java:38)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.glassfish.tyrus.core.AnnotatedEndpoint.callMethod(AnnotatedEndpoint.java:534)
	at org.glassfish.tyrus.core.AnnotatedEndpoint.access$100(AnnotatedEndpoint.java:87)
	at org.glassfish.tyrus.core.AnnotatedEndpoint$WholeHandler$1.onMessage(AnnotatedEndpoint.java:633)
	at org.glassfish.tyrus.core.TyrusSession.notifyMessageHandlers(TyrusSession.java:576)
	at org.glassfish.tyrus.core.TyrusEndpointWrapper.onMessage(TyrusEndpointWrapper.java:879)
	at org.glassfish.tyrus.core.TyrusWebSocket.onMessage(TyrusWebSocket.java:216)
	at org.glassfish.tyrus.core.frame.TextFrame.respond(TextFrame.java:139)
	at org.glassfish.tyrus.core.ProtocolHandler.process(ProtocolHandler.java:807)
	at org.glassfish.tyrus.core.TyrusWebSocketEngine$TyrusReadHandler.handle(TyrusWebSocketEngine.java:562)
	at org.glassfish.tyrus.container.grizzly.server.GrizzlyServerFilter$ProcessTask.execute(GrizzlyServerFilter.java:379)
	at org.glassfish.tyrus.container.grizzly.client.TaskProcessor.processTask(TaskProcessor.java:114)
	at org.glassfish.tyrus.container.grizzly.client.TaskProcessor.processTask(TaskProcessor.java:91)
	at org.glassfish.tyrus.container.grizzly.server.GrizzlyServerFilter.handleRead(GrizzlyServerFilter.java:215)
	at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
	at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284)
	at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201)
	at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133)
	at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112)
	at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
	at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:526)
	at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112)
	at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
	at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56)
	at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
	at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:591)
	at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:571)
	at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at path $
	at com.google.gson.internal.bind.JsonTreeReader.expect(JsonTreeReader.java:162)
	at com.google.gson.internal.bind.JsonTreeReader.beginObject(JsonTreeReader.java:87)
	at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:213)
	... 43 more

This is the error on the Client side:

java.lang.NullPointerException
	at com.musala.atmosphere.client.websocket.ClientDispatcher.getDeviceDescriptor(ClientDispatcher.java:198)
	at com.musala.atmosphere.client.Builder.getDevice(Builder.java:126)
	at com.atmosphere.others.ChangeOrientationTest_1.setUp(ChangeOrientationTest_1.java:54)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
	at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:24)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)

The expected behavior is to start the test without problems