Upgrade lib json_spirit from 4.03 to 4.06
Merge pull request #571 from cosmoharrigan/json_spirit

Upgrade lib json_spirit from 4.03 to 4.06
InheritanceToMemberRule was disabled in the default InferenceAgent. Re-enable it.
Inference history was disabled. Re-enable it, using the main atomspace, and don't 'copy' atoms.
formulas.py contains duplicate definitions of 'inheritanceFormula'. Disable one.
Update docstring formatting for GeneralEvaluationToMemberRule
Add inference agent for Tuffy 'smokes' example
Add inference agent for Tuffy 'smokes' example
Update __init__.py for module
Merge pull request #573 from cosmoharrigan/pln-updates

PLN: example agent for Tuffy 'smokes' problem, plus some small updates
Begin to add new AddAFSignal and RemoveAFSignals to AtomSpacePublisher
Multi-threaded background atomspace publisher
Add server commands to enable and disable AtomSpacePublisher signals while module is loaded
Replace Boost Property Trees with json_spirit to improve performance and preserve non-string types
In-progress updates to signal handling