finish some tests
	new files:   .c9revisions/*
	modified:   topics/about_arrays.js
	modified:   topics/about_asserts.js
	modified:   topics/about_assignment.js
	modified:   topics/about_control_structures.js
	modified:   topics/about_equality.js
	modified:   topics/about_numbers.js
	modified:   topics/about_objects.js
	modified:   topics/about_operators.js
	modified:   topics/about_prototypal_inheritance.js
	modified:   topics/about_prototype_chain.js
	modified:   topics/about_reflection.js
	modified:   topics/about_strings.js
	modified:   topics/about_truthyness.js