gradle: 2.14.1 -> 3.0, keep 2.14.1

pkgs/development/tools/build-managers/gradle/default.nix

···
     };
   };
 
-  gradleLatest = gradleGen rec {
+  gradle_latest = gradleGen rec {
+    name = "gradle-3.0";
+
+    src = fetchurl {
+      url = "http://services.gradle.org/distributions/${name}-bin.zip";
+      sha256 = "103z2nzlpc6x3mav0mqardd84rj1si718f6wpnpl8i273aa0dj9r";
+    };
+  };
+
+  gradle_2_14 = gradleGen rec {
     name = "gradle-2.14.1";
 
     src = fetchurl {
···
     };
   };
 
-  gradle25 = gradleGen rec {
+  gradle_2_5 = gradleGen rec {
     name = "gradle-2.5";
 
     src = fetchurl {

pkgs/top-level/all-packages.nix

···
   gotty = callPackage ../servers/gotty { };
 
   gradleGen = callPackage ../development/tools/build-managers/gradle { };
-  gradle = self.gradleGen.gradleLatest;
-  gradle25 = self.gradleGen.gradle25;
+  gradle = self.gradleGen.gradle_latest;
+  gradle_2_14 = self.gradleGen.gradle_2_14;
+  gradle_2_5 = self.gradleGen.gradle_2_5;
 
   gperf = callPackage ../development/tools/misc/gperf { };