Minor documentation improvements
Minor documentation improvements

AmeBel/opencog,andre-senna/opencog,andre-senna/opencog,andre-senna/opencog,AmeBel/opencog,AmeBel/opencog,andre-senna/opencog,andre-senna/opencog,andre-senna/opencog,AmeBel/opencog,AmeBel/opencog,AmeBel/opencog,andre-senna/opencog,AmeBel/opencog