Rename setter to indicate it's for initialization

Delay should be considered to be immutable.

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Rename ThreadSignal to Condition, it depends on Mutex

A condition should always be used together with a mutex. So, Mutex also has the relevant factory method.

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Added first version of ThreadTest

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Leave it to the VM how to store the name

Signed-off-by: Stefan Marr <git@stefan-marr.de>
In TruffleSOM, we use java.lang.Thread, which doesn't allow null.

Signed-off-by: Stefan Marr <git@stefan-marr.de>