Gradle version bump

Change-Id: If2da48b3dbfeabb1f7df9b07201251fc1e1ac417
Reviewed-on: http://gerrit.dmdirc.com/3897
Reviewed-by: Greg Holmes <greg@dmdirc.com>
Automatic-Compile: DMDirc Build Manager

build.gradle

@@ -96,5 +96,5 @@ buildscript {
 }
 
 task wrapper(type: Wrapper) {
-    gradleVersion = '2.0'
+    gradleVersion = '2.1'
 }

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Sun Sep 14 12:20:44 BST 2014
+#Sun Sep 14 12:37:42 BST 2014
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=http\://services.gradle.org/distributions/gradle-2.0-bin.zip
+distributionUrl=http\://services.gradle.org/distributions/gradle-2.1-bin.zip