Merge branch 'master' of github.com:Mpdreamz/NEST

Author: Mpdreamz

src/Nest.Tests.Unit/Search/Filter/Singles/GeoDistanceFilterJson.cs

@@ -27,7 +27,7 @@ public void GeoDistanceFilter()
 				filter : {
 					geo_distance: {
 						distance: 12.0,
-						distance_unit: ""km"",
+						unit: ""km"",
 						optimize_bbox: ""memory"",
 						origin: ""40, -70"",
 						_cache: true,

src/Nest/DSL/FilterDescriptor.cs

@@ -405,7 +405,7 @@ public BaseFilter GeoDistance(string field, Action<GeoDistanceFilterDescriptor>
 				dd.Add("distance", filter._Distance);
 
 				if (!string.IsNullOrWhiteSpace(filter._GeoUnit))
-					dd.Add("distance_unit", filter._GeoUnit);
+					dd.Add("unit", filter._GeoUnit);
 
 				if (!string.IsNullOrWhiteSpace(filter._GeoOptimizeBBox))
 					dd.Add("optimize_bbox", filter._GeoOptimizeBBox);