fix example/simple.js
fix example/simple.js

lib/metadata.js is looking for value 'entityType' in the entityset. This either needed to be changed to 'type' or the example updated

pofider/node-simple-odata-server,frostmann/node-simple-odata-server,fela98/node-simple-odata-server,hakandilek/node-simple-odata-server,timwis/node-simple-odata-server