Gradle: Update version registry links

Author: Turbo87

build.gradle

@@ -4,9 +4,10 @@ buildscript {
         kotlinVersion = '1.3.41'
 
         // see https://www.jetbrains.com/intellij-repository/releases/
+        // and https://www.jetbrains.com/intellij-repository/snapshots/
         intellijVersion = '2019.1.3'
 
-        // see https://plugins.jetbrains.com/idea/plugin/6884-handlebars-mustache
+        // see https://plugins.jetbrains.com/plugin/6884-handlebars-mustache/versions
         handlebarsPluginVersion = '191.6014.8'
     }