Add a Gradle task to build the nomulus tool

It'd be nice if we can separate out the tool to its own package and reduce the transitive dependencies that it pulls in. However since the entire core project is a dependency of the tool, it doesn't make any difference as we'd be pulling in core and all its transitive dependencies as well.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=224821931

gradle/build.gradle

@@ -44,8 +44,13 @@ subprojects {
     mavenCentral()
   }
 
+  def services = [':services:default',
+                  ':services:backend',
+                  ':services:tools',
+                  ':services:pubapi']
+
   // Set up all of the deployment projects.
-  if (project.name in ['default', 'backend', 'tools', 'pubapi']) {
+  if (services.contains(project.path)) {
 
     apply plugin: 'war'
 

gradle/core/build.gradle

@@ -444,3 +444,24 @@ test {
   maxParallelForks 5
 }.dependsOn(fragileTest, outcastTest)
 
+task nomulus(type: Jar) {
+  manifest {
+    attributes 'Main-Class': 'google.registry.tools.RegistryTool'
+  }
+  zip64 = true
+  baseName = 'nomulus'
+  version = null
+  from {
+    configurations.runtimeClasspath.collect {
+      it.isDirectory() ? it : zipTree(it)
+    }
+  }
+  // Excludes signature files that accompany some dependency jars, like
+  // bonuncycastle. It they are present, only classes from those signed jars are
+  // made available to the class loader.
+  // see https://discuss.gradle.org/t/signing-a-custom-gradle-plugin-thats-downloaded-by-the-build-system-from-github/1365
+  exclude "META-INF/*.SF", "META-INF/*.DSA", "META-INF/*.RSA"
+  with jar
+  dependsOn project(':third_party').jar
+}
+