rewrote logic to pull objectid in a way that works for both MapServer and FeatureServer feature layers

loop through the returned fields and pull the name of the field of type 'esriFieldTypeOID' and then write the name of the field to a private variable so that the loop isnt executed redundantly.

also found one last reference to WKID 4265 that should be 4326 in the main esri.leaflet source.