add coverage things

src/UriBuilder.Fluent.UnitTests/project.json

@@ -9,6 +9,7 @@
   },
 
   "frameworks": {
+    "net46": {},
     "netcoreapp1.0": {
       "dependencies": {
         "Microsoft.NETCore.App": {

src/UriBuilder.Fluent/TerribleDevUriExtensions.cs

@@ -21,7 +21,7 @@ namespace System
                 valuesEnum = new string[0];
             }
             var isfirst = string.IsNullOrWhiteSpace(bld.Query);
-            var intitialValue = isfirst ? "?" : $"{bld.Query}&";
+            var intitialValue = isfirst ? "" : $"{bld.Query.TrimStart('?')}&";
             var sb = new StringBuilder($"{intitialValue}{key}");
             var validValueHit = false;
             foreach(var value in valuesEnum)

src/UriBuilder.Fluent/project.json

@@ -6,7 +6,7 @@
   },
 
   "frameworks": {
-    "netstandard1.6": {
+    "netstandard1.3": {
       "imports": "dnxcore50"
     }
   }