fixed bug(s) with null property handling
fixed bug(s) with null property handling

pombreda/py2neo,nicolewhite/py2neo,technige/py2neo,nicolewhite/py2neo,fpieper/py2neo,fpieper/py2neo,nigelsmall/py2neo,pombreda/py2neo,technige/py2neo,nicolewhite/py2neo,pombreda/py2neo,fpieper/py2neo,nigelsmall/py2neo,technige/py2neo