pageObjectPackages configuration option is spelled incorrectly in error message
When you do not have any pageObject Packages defined, an error is thrown asking you to set the value pageObjectPackage. It should be pageObjectPackages.

Though at this point we should probably just search the entire program for them and mark where they exist for future use.
diff --git a/src/main/java/com/dougnoel/sentinel/apis/APIFactory.java b/src/main/java/com/dougnoel/sentinel/apis/APIFactory.java
index 21691c84..c0fa8d34 100644
--- a/src/main/java/com/dougnoel/sentinel/apis/APIFactory.java
+++ b/src/main/java/com/dougnoel/sentinel/apis/APIFactory.java
@@ -76,7 +76,7 @@ public class APIFactory {
 			}
 		}
 		if(api == null) {
-			throw new ConfigurationNotFoundException("The API you want to test could not be built. At least one Page object package is required to run a test. Please add a pageObjectPackage property to your conf/sentinel.yml configuration file and try again.");
+			throw new ConfigurationNotFoundException("The API you want to test could not be built. At least one Page object package is required to run a test. Please add a pageObjectPackages property to your conf/sentinel.yml configuration file and try again.");
 		}
 		return api;
 	}
diff --git a/src/main/java/com/dougnoel/sentinel/pages/PageFactory.java b/src/main/java/com/dougnoel/sentinel/pages/PageFactory.java
index 928e6935..49d564fd 100644
--- a/src/main/java/com/dougnoel/sentinel/pages/PageFactory.java
+++ b/src/main/java/com/dougnoel/sentinel/pages/PageFactory.java
@@ -66,7 +66,7 @@ public class PageFactory {
 	 */
 	public static Page buildOrRetrievePage(String pageName) throws PageNotFoundException, ConfigurationNotFoundException {
 		Page page = pages.get(pageName);
-		final String errorMessage = "The page you want to test could not be built. At least one Page object package is required to run a test. Please add a pageObjectPackage property to your conf/sentinel.yml configuration file and try again.";
+		final String errorMessage = "The page you want to test could not be built. At least one Page object package is required to run a test. Please add a pageObjectPackages property to your conf/sentinel.yml configuration file and try again.";
 		if (page != null) {
 			return page;
 		} else {
['src/main/java/com/dougnoel/sentinel/pages/PageFactory.java', 'src/main/java/com/dougnoel/sentinel/apis/APIFactory.java']