Bump py2neo version
Bump py2neo version

- fixes json encoding error

wcooley/neomodel,andrefsp/neomodel,robinedwards/neomodel,bleib1dj/neomodel,bleib1dj/neomodel,cristigociu/neomodel_dh,pombredanne/neomodel,robinedwards/neomodel,fpieper/neomodel