More changes to comments

More beautification of comment lines.
More prettifying of code
Fixed a bug where thread tried to kill already dead thread
Merge branch 'word_addressing'. Bunny adventure still seems to work.

Conflicts:
	lci-sim/Conversion.cpp
	lci-sim/Interpreter.cpp
	lci-sim/Interpreter.h
	lci-sim/MachineInstance.cpp
	lci-sim/MachineInstance.h