fix error related with atomspace.set_av
fix error related with atomspace.set_av

The error was:
AttributeError: 'opencog.atomspace.AtomSpace' object has no attribute 'set_av'

misgeatgit/opencog,inflector/opencog,andre-senna/opencog,shujingke/opencog,andre-senna/opencog,inflector/opencog,inflector/opencog,ruiting/opencog,andre-senna/opencog,shujingke/opencog,shujingke/opencog,yantrabuddhi/opencog,misgeatgit/opencog,misgeatgit/opencog,AmeBel/opencog,shujingke/opencog,misgeatgit/opencog,shujingke/opencog,ruiting/opencog,misgeatgit/opencog,inflector/opencog,ruiting/opencog,inflector/opencog,shujingke/opencog,andre-senna/opencog,misgeatgit/opencog,ruiting/opencog,ruiting/opencog,andre-senna/opencog,yantrabuddhi/opencog,ruiting/opencog,yantrabuddhi/opencog,AmeBel/opencog,inflector/opencog,AmeBel/opencog,AmeBel/opencog,yantrabuddhi/opencog,ruiting/opencog,inflector/opencog,AmeBel/opencog,inflector/opencog,misgeatgit/opencog,misgeatgit/opencog,misgeatgit/opencog,yantrabuddhi/opencog,AmeBel/opencog,andre-senna/opencog,AmeBel/opencog,andre-senna/opencog,yantrabuddhi/opencog,yantrabuddhi/opencog,shujingke/opencog