POM Cleanup

- Updated properties for ecr.repository, this should now be set in an external settings file or in the user's ~/.m2/settings.xml file.
- Bumped ECS plugin version.
- Added sonatype snapshot plugin repo.

pom.xml

@@ -15,9 +15,6 @@
         <dropwizard.version>1.3.8</dropwizard.version>
         <jackson.api.version>2.9.8</jackson.api.version>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <!--suppress UnresolvedMavenProperty -->
-        <ecr.repository>${env.ECR_REPOSITORY}</ecr.repository>
-
     </properties>
 
     <dependencies>
@@ -245,8 +242,10 @@
                         </goals>
                         <configuration>
                             <transformers>
-                                <transformer implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer"/>
-                                <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
+                                <transformer
+                                        implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer"/>
+                                <transformer
+                                        implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                                     <mainClass>org.whispersystems.textsecuregcm.WhisperServerService</mainClass>
                                 </transformer>
                             </transformers>
@@ -338,7 +337,7 @@
             <plugin>
                 <groupId>org.signal</groupId>
                 <artifactId>ecs-maven-plugin</artifactId>
-                <version>1.0-SNAPSHOT</version>
+                <version>1.1-SNAPSHOT</version>
                 <configuration>
                     <awsRegion>US_EAST_1</awsRegion>
                     <taskFamily>signal-service</taskFamily>
@@ -379,26 +378,19 @@
 
         </plugins>
 
-        <extensions>
-            <extension>
-                <groupId>com.gkatzioura.maven.cloud</groupId>
-                <artifactId>s3-storage-wagon</artifactId>
-                <version>1.6</version>
-            </extension>
-        </extensions>
     </build>
 
-    <repositories>
-        <repository>
-            <id>maven-staging-repo-snapshot</id>
-            <url>s3://maven-staging-repo.signal.org/snapshot</url>
-            <releases>
-                <enabled>false</enabled>
-            </releases>
+    <pluginRepositories>
+        <pluginRepository>
+            <id>sonatype-nexus-snapshots</id>
+            <url>https://oss.sonatype.org/content/repositories/snapshots</url>
             <snapshots>
                 <enabled>true</enabled>
             </snapshots>
-        </repository>
+        </pluginRepository>
+
+    </pluginRepositories>
+    <repositories>
         <repository>
             <id>gcm-server-repository</id>
             <url>https://raw.github.com/whispersystems/maven/master/gcm-server/releases/</url>