Make dev project configurable (#371)

* Make dev project configurable

We should not hardcode our dev project in the public config file.

* Remove the use of .ext when using external properties

They are only needed when defining properties.

db/build.gradle

@@ -73,12 +73,12 @@ ext {
   getCloudSqlCredential = { env, role ->
     def command =
         """gsutil cp \
-           gs://domain-registry-dev-deploy/cloudsql-credentials/${env}/${role}_credential.enc - | \
+           gs://${rootProject.devProject}-deploy/cloudsql-credentials/${env}/${role}_credential.enc - | \
            base64 -d | \
            gcloud kms decrypt --location global --keyring nomulus-tool-keyring \
            --key nomulus-tool-key --plaintext-file=- \
            --ciphertext-file=- \
-           --project=domain-registry-dev"""
+           --project=${rootProject.devProject}"""
 
     return execInBash(command, '/tmp')
   }

java_common.gradle

@@ -94,8 +94,8 @@ task initCoverageMinimums {
   ].asImmutable()
 
   rootProject.ext.getMinCoverage = { key ->
-    if (rootProject.ext.coverageMinimums.containsKey(key)) {
-      return rootProject.ext.coverageMinimums.get(key)
+    if (rootProject.coverageMinimums.containsKey(key)) {
+      return rootProject.coverageMinimums.get(key)
     }
     return 0.0
   }
@@ -117,7 +117,7 @@ jacocoTestCoverageVerification {
       //   or MISSEDRATIO
       // - The 'minimum' threshold, given as a fraction or a percentage (including '%')
       limit {
-        minimum = rootProject.ext.getMinCoverage(project.getName())
+        minimum = rootProject.getMinCoverage(project.getName())
       }
     }
   }

projects.gradle

@@ -15,7 +15,12 @@
 // Mapping from environment names to GCP projects.
 // Replace the values with the names of your deployment environments.
 
+// The projects to run your deployment Nomulus application.
 rootProject.ext.projects = ['production': 'your-production-project',
                             'sandbox'   : 'your-sandbox-project',
                             'alpha'     : 'your-alpha-project',
                             'crash'     : 'your-crash-project']
+
+// The project to host your development/deployment infrastructure. It hosts
+// things like release artifacts, CI/CD system, etc.
+rootProject.ext.devProject = 'your-dev-project'