Add initializer tests and move classpath files

The initializer tests verify that every non-optional initializer, this
includes Providers, is loadable.

Creating files under META-INF is not considered best practice. Smack's
configuration and provider files reside now in classpath directory
qualified by Smack's package namespace.

experimental/src/main/java/org/jivesoftware/smackx/ExperimentalProviderInitializer.java

@@ -14,9 +14,9 @@
  * limitations under the License.
  */
 
-package org.jivesoftware.smackx.experimental;
+package org.jivesoftware.smackx;
 
-import org.jivesoftware.smack.provider.UrlProviderFileInitializer;
+import org.jivesoftware.smack.initializer.UrlProviderFileInitializer;
 
 /**
  * Initializes the providers in the experimental code stream.
@@ -28,6 +28,6 @@ public class ExperimentalProviderInitializer  extends UrlProviderFileInitializer
 
     @Override
     protected String getFilePath() {
-        return "classpath:META-INF/experimental.providers";
+        return "classpath:org.jivesoftware.smackx/experimental.providers";
     }
 }

experimental/src/main/java/org/jivesoftware/smackx/WorkgroupProviderInitializer.java

@@ -0,0 +1,11 @@
+package org.jivesoftware.smackx;
+
+import org.jivesoftware.smack.initializer.UrlProviderFileInitializer;
+
+public class WorkgroupProviderInitializer  extends UrlProviderFileInitializer {
+
+    @Override
+    protected String getFilePath() {
+        return "classpath:org.jivesoftware.smackx/workgroup.providers";
+    }
+}

experimental/src/main/java/org/jivesoftware/smackx/workgroup/WorkgroupProviderInitializer.java

@@ -1,11 +0,0 @@
-package org.jivesoftware.smackx.workgroup;
-
-import org.jivesoftware.smack.provider.UrlProviderFileInitializer;
-
-public class WorkgroupProviderInitializer  extends UrlProviderFileInitializer {
-
-    @Override
-    protected String getFilePath() {
-        return "classpath:META-INF/workgroup.providers";
-    }
-}

experimental/src/test/java/org/jivesoftware/smackx/ExperimentalProviderInitializerTest.java

@@ -0,0 +1,15 @@
+package org.jivesoftware.smackx;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+public class ExperimentalProviderInitializerTest {
+
+    @Test
+    public void testExperimentalProviderInitialzer() {
+        ExperimentalProviderInitializer epi = new ExperimentalProviderInitializer();
+        epi.initialize();
+        assertTrue(epi.getExceptions().size() == 0);
+    }
+}

experimental/src/test/java/org/jivesoftware/smackx/WorkgroupProviderInitializerTest.java

@@ -0,0 +1,15 @@
+package org.jivesoftware.smackx;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+public class WorkgroupProviderInitializerTest {
+
+    @Test
+    public void testWorkgroupProviderInitializer() {
+        WorkgroupProviderInitializer wpi = new WorkgroupProviderInitializer();
+        wpi.initialize();
+        assertTrue(wpi.getExceptions().size() == 0);
+    }
+}