Addressing issue #30 by setting the distributionSha256Sum

Author: ianblenke

torgi/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-all.zip
+distributionSha256Sum=9af7345c199f1731c187c96d3fe3d31f5405192a42046bafa71d846c3d9adacb