ButtplugFutureStateShared allows data race to (!Send|!Sync) objects

ButtplugFutureStateShared<T> implements Send & Sync regardless of T.

If T: !Send for ButtplugFutureStateShared<T>, it is possible to move non-Send types across thread boundaries (e.g. T=Rc<T>) and lead to undefined behavior.
If T: !Sync for ButtplugFutureStateShared<T>, it is possible to cause data race to T (e.g. T=Arc<Cell<_>>) and lead to undefined behavior.

The flaw was corrected in version 1.0.4 by removing manual implementations of Send/Sync for ButtplugFutureStateShared<T> to let rustc generate auto trait implementations with correct trait bounds on T.