Add snapshot repo to examples pom.xml

When running the examples from the distribution the example poms need to
find the top level activemq-pom.  For snapshot releases this will only
exist in the snapshot repo.  In additon we include the snapshot plugins
repo for the activemq-maven-plugin

examples/pom.xml

@@ -38,6 +38,28 @@ under the License.
       <skipStyleCheck>true</skipStyleCheck>
    </properties>
 
+   <repositories>
+      <repository>
+          <id>apache.snapshots</id>
+          <name>Apache Development Snapshot Repository</name>
+          <url>https://repository.apache.org/content/repositories/snapshots/</url>
+          <snapshots>
+              <enabled>true</enabled>
+          </snapshots>
+      </repository>
+   </repositories>
+
+   <pluginRepositories>
+      <pluginRepository>
+         <id>apache.snapshots</id>
+         <name>Apache Development Snapshot Repository</name>
+         <url>https://repository.apache.org/content/repositories/snapshots/</url>
+         <snapshots>
+            <enabled>true</enabled>
+         </snapshots>
+      </pluginRepository>
+   </pluginRepositories>
+
    <modules>
       <module>core</module>
       <module>jms</module>