Restored a line which was inadvertantly deleted.
Fixed some problems with lesson initialization.
Fixed failure to track variables created by side effects, e.g., sourcing a figure file. Requires that all variables created by side effects in the lesson must be "declared" in initLesson.R if they should be tracked.
Fixed incompatibility with custom tests in certain lessons. Code may be OK now, but don't count on it.
Fixed oversight in answer tests.
minor change
possible fix to "play" bug.
incremented to version 2.2.8; added news item