Move main executable source to its own directory (#248)

* Move main executable files to their own directory

* Adapt the build to the new file structure

... and fix some weird #include's that were relying on the project root
being an include directory.

Ja2/MPJoinScreen.h

@@ -0,0 +1,32 @@
+#ifndef _MP_JOIN_SCREEN_H_
+#define _MP_JOIN_SCREEN_H_
+
+#include <vfs/Core/vfs.h>
+
+namespace vfs{
+	class PropertyContainer;
+}
+
+class CUniqueServerId
+{
+public:
+	vfs::String const& getServerId(vfs::Path dir, vfs::PropertyContainer* props = NULL);
+
+	static void uniqueRandomString(vfs::String& str);
+private:
+	vfs::String _id;
+};
+
+extern CUniqueServerId s_ServerId;
+
+UINT32	MPJoinScreenInit( void );
+UINT32	MPJoinScreenHandle( void );
+UINT32	MPJoinScreenShutdown( void );
+
+void	SaveJoinSettings(bool ReSaving);
+
+void	MpIniExists();
+
+
+
+#endif