added README for resolving issue with integration tests

circus-train-integration-tests/README.md

@@ -0,0 +1,27 @@
+## Running the integration tests
+
+Generally the integration tests should "just work" when run via Maven on the command line and in an IDE. However we have seen issues where 
+an IDE may struggle with the shading and relocating of certain classes which in turn causes certain tests to fail. This manifests itself in 
+tests that pass on the command line but fail in the IDE, usually with a failure like
+```
+java.util.ServiceConfigurationError: org.jclouds.providers.ProviderMetadata: Provider org.jclouds.azureblob.AzureBlobProviderMetadata could not be instantiated
+	at java.util.ServiceLoader.fail(ServiceLoader.java:232)
+	at java.util.ServiceLoader.access$100(ServiceLoader.java:185)
+	...
+Caused by: java.lang.NoClassDefFoundError: com/google/common/base/MoreObjects$ToStringHelper
+    ...
+Caused by: java.lang.ClassNotFoundException: com.google.common.base.MoreObjects$ToStringHelper
+	at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
+	at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
+	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352)
+	at java.lang.ClassLoader.loadClass(ClassLoader.java:351)    
+```
+This indicates that the shading and relocation (in the above example of a Guava class) hasn't been activated in the IDE. One solution to this is to 
+rebuild the entire project using Maven on the command line and then re-run the tests in the IDE. The following steps should achieve that: 
+
+1. Run `mvn -DskipTests install` in the top-level Circus Train parent project (this should repackage and relocate classes using the Maven 
+plugin and generate the correct class files in the produce jar artifacts).
+2. Refresh the project in the IDE (this should get the IDE to pick up the above classes via their artifacts).
+3. Close the `circus-train-common-test` module project - this will get the IDE to use the jar file for this which contains the shaded classes 
+   instead of the source code directly.
+4. Run the integration tests (which should now pass!)