Unable to re-initialize platform after it has been uninitialized

[mmarich]

After calling Platform.initialize() then performing actions with an ActionCamera instance and finally calling Platform.uninitialize(), any subsequent to Platform.initialize() results in an IllegalThreadStateException being thrown.

When looking at decompiled source, it appears that Platform gets the singleton instance of AsyncSocketWorkThread from AsyncSocketWorkThread.getInstance().

A work around is to never call Platform.uninitialize(), since Platform.initialize() appeard to check if it has been initialized. That said, there is now a zombie thread hanging around.

I believe that AsyncSocketWorkThread.getInstance() should be modified so that dead threads are discarded.