LibCore: Put all classes in the Core namespace and remove the leading C

I've been wanting to do this for a long time. It's time we start being
consistent about how this stuff works.

The new convention is:

- "LibFoo" is a userspace library that provides the "Foo" namespace.

That's it :^) This was pretty tedious to convert and I didn't even
start on LibGUI yet. But it's coming up next.

Servers/AudioServer/ASClientConnection.cpp

@@ -48,7 +48,7 @@ void ASClientConnection::for_each(Function<void(ASClientConnection&)> callback)
         callback(connection);
 }
 
-ASClientConnection::ASClientConnection(CLocalSocket& client_socket, int client_id, ASMixer& mixer)
+ASClientConnection::ASClientConnection(Core::LocalSocket& client_socket, int client_id, ASMixer& mixer)
     : IClientConnection(*this, client_socket, client_id)
     , m_mixer(mixer)
 {

Servers/AudioServer/ASClientConnection.h

@@ -37,7 +37,7 @@ class ASClientConnection final : public IClientConnection<AudioServerEndpoint>
     , public AudioServerEndpoint {
     C_OBJECT(ASClientConnection)
 public:
-    explicit ASClientConnection(CLocalSocket&, int client_id, ASMixer& mixer);
+    explicit ASClientConnection(Core::LocalSocket&, int client_id, ASMixer& mixer);
     ~ASClientConnection() override;
 
     void did_finish_playing_buffer(Badge<ASBufferQueue>, int buffer_id);

Servers/AudioServer/ASEventLoop.cpp

@@ -31,7 +31,7 @@
 #include <unistd.h>
 
 ASEventLoop::ASEventLoop()
-    : m_server(CLocalServer::construct())
+    : m_server(Core::LocalServer::construct())
 {
     bool ok = m_server->take_over_from_system_server();
     ASSERT(ok);

Servers/AudioServer/ASEventLoop.h

@@ -37,7 +37,7 @@ public:
     int exec() { return m_event_loop.exec(); }
 
 private:
-    CEventLoop m_event_loop;
-    RefPtr<CLocalServer> m_server;
+    Core::EventLoop m_event_loop;
+    RefPtr<Core::LocalServer> m_server;
     ASMixer m_mixer;
 };

Servers/AudioServer/ASMixer.cpp

@@ -31,7 +31,7 @@
 #include <pthread.h>
 
 ASMixer::ASMixer()
-    : m_device(CFile::construct("/dev/audio", this))
+    : m_device(Core::File::construct("/dev/audio", this))
     , m_sound_thread(
           [this] {
               mix();
@@ -39,7 +39,7 @@ ASMixer::ASMixer()
           },
           "AudioServer[mixer]")
 {
-    if (!m_device->open(CIODevice::WriteOnly)) {
+    if (!m_device->open(Core::IODevice::WriteOnly)) {
         dbgprintf("Can't open audio device: %s\n", m_device->error_string());
         return;
     }

Servers/AudioServer/ASMixer.h

@@ -106,7 +106,7 @@ private:
     WeakPtr<ASClientConnection> m_client;
 };
 
-class ASMixer : public CObject {
+class ASMixer : public Core::Object {
     C_OBJECT(ASMixer)
 public:
     ASMixer();
@@ -125,7 +125,7 @@ private:
     pthread_mutex_t m_pending_mutex;
     pthread_cond_t m_pending_cond;
 
-    RefPtr<CFile> m_device;
+    RefPtr<Core::File> m_device;
 
     LibThread::Thread m_sound_thread;