In order to better model content close vs destroy, add the concept
of closing a thread to the JS interface.
Signed-off-by: Daniel Silverstone <dsilvers@digital-scurf.org>
In preparation for proper splitting of Javascript support into
heaps and threads, this renames the types and corrects the no-js
builds to still work. At this time no substantive change in
semantics exists, and the duktape build won't work.
Signed-off-by: Daniel Silverstone <dsilvers@digital-scurf.org>
